Sliding Rocks Bemuse Scientists

An anonymous reader writes "Scientists can't figure out why these rocks — weighing up to several hundred pounds each — slide across a dry lake bed. The leading theory proposes that wind moves the rocks after a rain when the lake bed consists of soft and very slippery mud.

Comments

Mark Newman Poster

[stoolpigeon]

Mark Newman has a very nice sliding rock poster with a good shot of rock and trail in a variety of sizes.

Re:Mark Newman Poster

[An ominous Cow art]

I was there in August this year, and it was quite windy. It's very easy to imagine that if the ground had been muddy, the wind could slide the rocks around.

Re:Mark Newman Poster

[Anonymous Coward]

you were in Mark Newman's poster?

Re:Mark Newman Poster

[An ominous Cow art]

Why, yes. Yes, I was.

But no, really, I was at the Racetrack playa in Death Valley National Park. I'd post pictures, but the ones in TFA cover it pretty well. Although I do have a nice close-up of the ground texture.

Re:Mark Newman Poster

[Anonymous Coward]

I dunno. It seems to me that it's just another crop circle thing.

1) many rocks didn't penetrate to the bottom of the mud pieces, which to me says the mud wasn't totally soggy when the rock was moved. How can the top be so soggy that the rock slides, but the bottom still be hard?

2) One of the rock pictures had rubble next to it that looked like it was created from already dry clay crumbled up.

Just seems to me that instead of crazy rocks sliding round on their own, some damn kids were up there fucking round with rocks.

Re:Mark Newman Poster

[Just Some Guy]

It's very easy to imagine that if the ground had been muddy, the wind could slide the rocks around.

There are few sights as graceful as the majestic stoneships with their rocky sails gliding across the bounding main.

OK, I can possibly imagine storm winds so ferocious that they can drag rocks across a rough surface. I just can't imagine said surface being neatly lined and clean-edged afterward. If the mud were soft enough for the rocks to move across it easily, wouldn't it be prone to the soil equivalent of whitecaps with little ripples across it?

Re:Mark Newman Poster

[MillionthMonkey]

Don't go in August! That's crazy! The best times to go to Death Valley are March and October. The temperature is much nicer and the place is less crowded. We were there last month and all the waitresses and hotel owners in the surrounding towns were saying the same thing: "You picked a great time to come... the weather is getting nice and all the Europeans are gone." [Actual quote]

It could be constraints imposed by when they get their vacations, but one of the most well known phenomena in Death Valley is the appearance of thousands of European and Asian tourists during the hottest months of the year. We usually go once every one or two years and on the last few visits we saw that a lot of places had instituted a policy where the tip is included in the bill (so you pay taxes on it) but only in the summer months, because of the difference in tipping behavior.

One thing that was really nice about Death Valley- every place we stayed had excellent wireless.

Re:Mark Newman Poster

[stoolpigeon]

In the desert the ground is really, really hard. It is completely plausible that a thin layer on the top could be slimy mud, while hard clay lies beneath.
 
I don't think you appreciate how remote this site is and what an effort it would be to pull off something like that. I really don't think it is someone messing around or that the wind theory is as unlikely as you think.

Re:Mark Newman Poster

[radish]

Yeah, I mean heaven forbid tourists actually come and spend money at their tourist-related businesses. I can imagine they're so glad when all that money goes back where it came from! Then their hotels can be nice and empty like they should be.

Re:Mark Newman Poster

[ChameleonDave]

Indeed.

When my heavy beer glass gets a tiny bit of water between it and the hard table, it starts sliding around all by itself, with no wind at all. I can imagine that these stones slide similarly.

Re:Mark Newman Poster

[clam666]

In soviet desert, rocks move you?

Re:Mark Newman Poster

[insertwackynamehere]

I thought the exact same thing when reading the summary sans beer

Re:Mark Newman Poster

[Anonymous Coward]

Hey nobody said the proprietors were turning them away. That doesn't automatically mean the visitors weren't assholes though. Your snarky attitude would probably resonate quite well with the aforementioned Euros...

And before you go all "but their culture views tipping differently, it's not their fault" on me, isn't our stubborn adherence to our cultural norms when visiting their countries the basis for the whole "ugly American" tag?

Re:Mark Newman Poster

[An ominous Cow art]

I was in Las Vegas that week for DefCon (which I wound up skipping anyway) and a Rush concert. Apparently the Classic Gaming Expo was there also during that period, but I didn't know it was in LV this year until I read a Slashdot story after it was over, sadly.

I stayed in aptly-named Furnace Creek, and two years ago stayed in Stovepipe Wells. I didn't mind the heat so much- 120' the first day, 115 the rest of the time I was there. I had a lot of cold water with me at all times.

I don't mind the Europeans - it was fun trying to figure out what the German-speakers were saying, based on my 2 years of classes in high school, 23+years ago...

Thanks for the tip on tipping :-).

Re:Mark Newman Poster

[Basehart]

It's not just beer. I was bathing the other day and my pint sized glass of heavily iced water all of a sudden moved across the smooth plastic surface of the toilet seat lid and fell to the floor.

The toilet seat lid was covered in a fine layer of condensation from the bath water at the time.

I'm betting if the stones are cooled way down to almost freezing by the wind, or maybe frozen overnight and still cold when the rains hit, and the top surface of the mud turns into a slurry of fine particles, the stone will move around all on its own just like my cold glass of water on a fine layer of condensation.

Either that or space aliens.

Re:Mark Newman Poster

[Anonymous Coward]

Of course, we all know what this really means....

Re:Mark Newman Poster

[vought]

Just seems to me that instead of crazy rocks sliding round on their own, some damn kids were up there fucking round with rocks. Considering how difficult it is to get out to the Racetrack, I doubt this. Otherwise, I would think someone might camp out there during a storm and find out if they really skate around on their own.

Problem is that storms come up rarely but suddenly there (usually) and it takes almost two hours to get to the Racetrack from the nearest paved road - three hours from the Death Valley visitor's center - and if you get out there before a storm, there's no guarantee that even a very capable 4x4 will get you back afterwards.

Re:Mark Newman Poster

[AtomicRobotMonster]

I'm going next week to ride around in the desert for 3 days. Should be nice and cold at night.

Re:Mark Newman Poster

[Roger W Moore]

Problem is that storms come up rarely but suddenly there (usually) and it takes almost two hours to get to the Racetrack from the nearest paved road - three hours from the Death Valley visitor's center - and if you get out there before a storm, there's no guarantee that even a very capable 4x4 will get you back afterwards.

Isn't this what remote camera's were invented for? I doubt this location is so remote that there isn't some way to link it up or at least to store the data and then periodically retrieve it. The question is have these rocks moved recently or is this a rare (i.e. once/century say) type occurance?

Re:Mark Newman Poster

[Anonymous Coward]

In many places the tipping thing is stupid. Why should I pay extra for someone to just do their job?

If the place is not paying that person enough for the job they should go work somewhere else.

Re:Mark Newman Poster

[vought]

I doubt this location is so remote that there isn't some way to link it up or at least to store the data and then periodically retrieve it. It'd cost a bundle, and might not work (rain, when it comes, is very heavy) during the kind of storms that produce the stone mobility. If you can't see the rocks from the only place that you can mount a camera, it's not going to help much. Take a look at where the Racetrack is - aside from a two-hour, 27-mile drive into a box canyon that demands a well-equipped vehicle, supplies, and some expensive equipment, I don't see what is stopping anyone from setting up a webcam.

  3641'0.10"N, 11733'58.77"W

The webcams in Yosemite are all five minutes from the road. A webcam in the Racetrack, while technically feasible, would take a fair bit of money and time to set up for the possibility of no payoff.

Re:Mark Newman Poster

[Anonymous Coward]

No, that's your adherence to a diet of Twinkies and Lutherburgers.

Re:Mark Newman Poster

[samwichse]

Hah!

Sounds like the perfect job for a grad student!

"All right, good to have you on board. Now you're going to camp out and stare at these rocks in Death Valley for 6 months. Bring your findings back to the committee, where we'll tell you we dislike your statistical methods (Zero movement? Where are the error bars on that?)"

Sam

Re:Mark Newman Poster

[torkus]

I love places that try to require a tip on the bill. Those places, shoudl I happen to wind up at one unknowingly, will never get a cent for a tip. I'll figure out the actual check total and pay exactly that. The can go scratch on the tip for being retarded about it.

Re:Mark Newman Poster

[Anonymous Coward]

A webcam in the Racetrack, while technically feasible, would take a fair bit of money and time to set up for the possibility of no payoff.

Sounds like science!

Seriously, we are talking about a nation where people joke about things like this: 24. You think nothing of getting up at 4am, driving for 5 hours, sitting in a traffic backup for 3 hours, baking in the sun, spending 5 hours to get out of the parking lot, driving 5 hours home, getting up the next morning at 5 am, going to work on 3 hours sleep, and telling everybody what a GREAT time you had.

What's so hard about driving out to a remote location and placing a few cameras? And how about a recording GPS unit and an anemometer mounted ON ONE OF THE ROCKS?

It sounds like fun, and it would only take a few years to get results. Compared to raising children the cost is low and the results are fast.

Re:Mark Newman Poster

[thejuggler]

At least you would have plenty of solar power to keep the electronics powered. It should be easy enough to setup the equipment needed to do this since we have been able to keep other remote cameras running in harsh climates for years. Mars rovers come to mind.

Re:Mark Newman Poster

[vought]

It sounds like fun, and it would only take a few years to get results. Compared to raising children the cost is low and the results are fast. I agree. You do it.

Re:Mark Newman Poster

[jamesh]

Perhaps this is how the pyramids were built... hardly any effort involved at all, they just waited until the wind was behind them and coaxed the rocks into their location with some slippery mud...

Re:Mark Newman Poster

[MillionthMonkey]

I love places that try to require a tip on the bill. Those places, shoudl I happen to wind up at one unknowingly, will never get a cent for a tip. I'll figure out the actual check total and pay exactly that. The can go scratch on the tip for being retarded about it.

In Death Valley? They'll remember your face and tomorrow you'll end up driving an extra 50 miles for lunch.

Re:Mark Newman Poster

[iminplaya]

...my pint sized glass of heavily iced water all of a sudden moved across the smooth plastic surface...

Poltergeist!

Re:Mark Newman Poster

[Mantis8]

Here's another pic of a sliding rock: http://www.pbase.com/devonshire/image/76469804

Re:Mark Newman Poster

[eonlabs]

"there's no guarantee that even a very capable 4x4 will get you back afterwards"

So ride the rocks!

Re:Mark Newman Poster

[An ominous Cow art]

The Racetrack is isolated, but not *that* isolated. It was a couple hour's drive in a rented SUV to get there. I don't think you could leave expensive equipment there and expect it to be unmolested.

Now, an instrument package disguised as a rock might work...

Re:Mark Newman Poster

[blahplusplus]

"I really don't think it is someone messing around or that the wind theory is as unlikely as you think."

I think people should stop thinking of it as "wind" and start thinking of it *as an ocean of air* that has currents and waves like the *real ocean*.

Re:Mark Newman Poster

[Annoying]

I remember a story a few years back about a guy in new york who refused to pay a tip even though the menu said a gratuity would be added to the bill, the proprietor called the police and the guy was arrested for theft of services. If you're going to try that, just be sure the addition of the gratuity wasn't written in fine print somewhere on the menu, or hope the proprietor doesn't care enough to bother.
Some googling revealed that the new york man was eventually let go after a judge determined that he could not be assessed a mandatory tip, but also while googling I found mention of texas law which specifically mentioned mandatory gratuities and upholds them.

Re:Mark Newman Poster

[colmore]

Not tipping is a gestural communication that says to the world "my parents didn't go to college."

Seriously dude, it's low class. 20% for everything everywhere, things in America tend to cost less than they should anyway (go out to dinner in any other first world country on a local salary). If service was slow, it's the kitchens fault, or someone who isn't serving you didn't show up. If the order was wrong, it's still likely the fault of the kitchen / understaffing. Or maybe your server has only worked their for a week. Punishing new staff is a good way never to get old staff. Whatever the problem is, if they're polite or even cordial, it's still a full tip.

Anyone who has to stand up and pretend to be happy while dealing with the public should get tips. I'd tip at retail if they'd put out a cup. The public is horrible. Customers are like children. Restaurant patrons are worse. Maintaining a positive attitude in that situation requires compensation that is visible and frequent.

Tip dammit. If they have to require it on the bill, then they probably have the unfortunate luck to have an unusually high cheap asshole component in their customer base. And the manager that set the policy won't ever see your lack of tipping. You just made someone's minimum wage hour worse. Way to go.

Re:Mark Newman Poster

[darthflo]

So, 20% on everything. 20% if service's slow, the food sucks and nobody makes you feel welcome; 20% for great attentive service, great food at competitive prices and nice atmosphere?
With the U.S.' minimum wage differences between tipped and untipped workers I see the point of tipping 5-10% for an acceptable experience, but 20% is - imo - reserved for when service was great. I paid what's on the bill, thus I paid the goods and services I received. Everything after that point should be a way to express my gratitude for a better-than-average experience. Also I'd really like to see the car salesman's face after you tipped him $4k on an $20k car and your real estate agent's expression after you cut her an $80k cheque for that nice $400k home.

Re:Mark Newman Poster

[Anonymous Coward]

I for one welcome our new sliding rock overlords

Re:Mark Newman Poster

[Anonymous Coward]

xD
Damn! people in my office now really think I'm crazy, I've been laughing like a maniac for almost 10 minutes non stop

Re:Mark Newman Poster

[Anonymous Coward]

Maybe it's the lake that's moving, and the rocks are staying still.

Re:Mark Newman Poster

[skaimauve]

YouTube has a cool video about the"ice theory" http://www.youtube.com/watch?v=u1hoiHvOeGc

Re:Mark Newman Poster

[colmore]

Well obviously sales that work on commission are covering the tipping angle with a different setup.

But 20% for acceptable service or service that had problems that didn't relate to your server. Most negative restaurant experiences don't come from the person writing down your order and handing you your plates. Undertipping because of slow service is venting frustration, not punishing whoever is at fault.... the person at fault may well be the manager who wrote an unreasonable schedule or the other server who is at home stoned leaving your undertipped staffer covering twice the workload.

15% was the polite minimum years ago, 20% in expensive cities. But the cost of living has gone up a lot since the early 90s, and wages at the bottom rung haven't. And since we don't have a society that can run without bottom-tier jobs, it's good civics to update custom.

Re:Mark Newman Poster

[Dancindan84]

I'm betting if the stones are cooled way down to almost freezing by the wind, or maybe frozen overnight and still cold when the rains hit, and the top surface of the mud turns into a slurry of fine particles, the stone will move around all on its own just like my cold glass of water on a fine layer of condensation. That's somewhat what I was thinking. When I saw it the first thing that came to mind (being a Canadian) was curling. A frozen rock sliding on a thin layer of mud would work fairly similarly to a rock sliding on ice, except leaving the trail in the mud.

Re:Mark Newman Poster

[IndustrialComplex]

15% was the polite minimum years ago, 20% in expensive cities. But the cost of living has gone up a lot since the early 90s, and wages at the bottom rung haven't. And since we don't have a society that can run without bottom-tier jobs, it's good civics to update custom.

Except that a % doesn't have to increase to match cost of living increases. The fact that it is a percentage automatically adjusts it for cost of living.

$10 meal in 1950 at 20%?.....$2
$100 meal in 2007 at 20%.....$20

So no, tip %'s don't have to increase with the 'times'.

Re:Mark Newman Poster

[RockDoctor]

I doubt this location is so remote that there isn't some way to link it up or at least to store the data and then periodically retrieve it.

It'd cost a bundle, and might not work (rain, when it comes, is very heavy)

At least two people on Slashdot have visited the site (OK, Slashdot does have a rather abnormal readership), which takes it from "really remote" to just "moderately remote". I've been to bits of cave where (literally) more people have walked on the Moon, and I wouldn't describe tham as particularly remote. Hard and not particularly rewarding to get to, but hardly "remote" in the way that large parts of Antarctica are. Hmmm, bad example - I was at a conference a couple of weeks ago where models for oil exploration in Antarctica were being discussed, which takes the level of remoteness down somewhat.
A combination of solar cells, battery-backed storage, and a modicum of intelligence in the machine to do motion detection should make a reasonably robust surveillance system perfectly feasible. And if the place is *only* 3 hours by vehicle from a national park centre of some sort then there's going to be enough traffic for a "park ranger / guide / guard" person to get in and dump the data several times a year.
Hell, I've heard enough crazy theories about this place over the years (I think von Daniken was the first person I heard about it from!) that I'd be willing to stump up a couple of hundred bucks into the pot to get an answer. Or I'd try pitching the idea to a TV company for an hour of Discovery Channel filler.

Re:Mark Newman Poster

[Anonymous Coward]

Read up on wage laws. In a lot of places, like restaurants, the folks who are waiting on the tables are making less then minimum wage and the rest of their salary comes from tips. (This varies state by state.) And "who do you tip" varies by culture. Here in the U.S. it's considered proper to tip waitresses / waiters, food delivery folks, and anyone who does you a personal service (not counting folks who earn commissions on sales). Hairdressers, barbers, taxi drivers - people whose job is to deal with your whims.

Personally, 10% is the absolute minimum that I'll tip - and the waitress will have to be really rude in order to earn that. Otherwise, I usually calculate 15% or 20% and then round up to the next dollar.

But if it's a place that I eat at regularly (like the local diner) where the normal tip would only be $1 - I prefer to put a bit extra down on the table. The extra money doesn't bother me at all and it makes the wait staff happier. Plus it pays off down the road in improved service.

And if you feel like tipping extra is a burden, then maybe you shouldn't be eating out so often.

Re:Mark Newman Poster

[jim_redwagon]

Discovery Channel filler? is there really such a thing? ;-)

Re:Mark Newman Poster

[BigDogCH]

Yeah, but you won't know where the rock is when you return! It will have moved!

Re:Mark Newman Poster

[slashname3]

It's not the wind. It is the earth rotating under the rocks. Not sure of the latitude of the location but the earth is rotating at something around 1000 miles per hour at the equator.

Re:Mark Newman Poster

[Skreems]

If they inform you of the policy before you eat, either verbally or through some note on the menu or visible sign near the entrance, what you're doing is technically theft.

Re:Mark Newman Poster

[zaf]

Sunrise Earth?
(not sure if this is affiliated with Discovery Channel, though)

Re:Mark Newman Poster

[torkus]

Wrong, for several reasons.

First - check case law. A judge has ruled on a similar case where an individual declined to pay a "mandatory" tip and was arrested for it. The judge ruled that a tip is just that - an optional gratuity and can not be required.

Second - posting a 'sign' (it's usually a very small line at the bottom of the last page of the menu) still does not make something required or law. Especially if it violates existing law a/o case law.

If the waiter verbally informs the entire party and everyone CONSENTS to the charge then that's a different story.

Re:Mark Newman Poster

[Wite_Noiz]

difference in tipping behavior

As a European, I'm intrigued as to what the different behaviours are?

Re:Mark Newman Poster

[general scruff]

That wouldn't explain the change in direction of some of the rock paths. Do you know of any other similar phenomena caused by the earths rotation? Its a very interesting theory! =)

Re:Mark Newman Poster

[torkus]

HAHAHAHA. Ok, so -1 troll but i'll respond anyway. You're clearly someoen who's pissed off they do (or did) work a service job that subsists off tips.

So let me get this straight - you want me to pay your salary instead of your employer. By itself, stupid but that's 'how things are'. Fine. Moving on...

First off, saying '20% for everything' means you're used to being the one getting tipped. It shows. You're greedy. That said, if service is good I will tip 18-20%. If the service is NOT good I will NOT tip anywhere near 20%. I'm not stupid, I can tell when a waiter is inattentive as opposed to the kitchen screwing everything up. I've had my meal come out wrong !twice! and still left a good tip because the waiter was actually there, available, explained the problem and did his/her best to fix it. I've had other times where i'm watching a waiter BS with his friends and then my food comes out cold and (god forbid) i ask for a drink refill and it takes 10 minutes. Guess what? He's getting 5% (not nothing so me might think I forgot) to make a point.

Beyond that. If you want to cry about "Anyone who has to stand up and pretend to be happy while dealing with the public" well then those people SHOULD GET A DIFFERENT JOB! If you hate the public, don't get a service job. It's THAT SIMPLE. You don't get sympathy (and money) from me because you don't like your job. There are plenty of people who are happy and keep a good attitude. They get good tips in general.

Again though, TIPS are reward/compensation for GOOD service. You may consider it mandatory but it's NOT. Welcome to merrit-based pay. You suck, you get jack. You're good, you can easily exceed your co-workers. If you don't like it, get a 9-5 and quit crying.

To finish...I just have to point out this one: "Maintaining a positive attitude in that situation requires compensation that is visible and frequent". HAHAHAHAHA. You know what? Learn some people skills. It's not like every person I deal with in my job is a perfect gentleman or lady. It's not like everyone, every time, is as considerate as they can be or even understands a situation completly. I deal with assholes all the time and i'm not a waiter! Guess what. No Vice President is going to hand me a $20 for dealing with his inane questions during my presentation.

Re:Mark Newman Poster

[torkus]

LOL. Ok, while i'll argue plenty of other points and crying about tips, I bow to your logic here.

I'm used to NYC and it's suburbs. You can't spit without it landing on somewhere to eat around here. Death Valley is clearly different :)

That said, freedom of choice. I choose not to tip, they choose not to serve me tomorrow. Fair enough!

Re:Mark Newman Poster

[dedalus2000]

It's not the wind. It is the earth rotating under the rocks. Not sure of the latitude of the location but the earth is rotating at something around 1000 miles per hour at the equator.

Is that why every time I jump straight up I always land 500 feet west?

Re:Mark Newman Poster

[Anonymous Coward]

the folks who are waiting on the tables are making less then minimum wage and the rest of their salary comes from tips

And the fact this f'd up wage is legal forces me to tip? No- make the business pay (at least) minimum wage, and drop this 'tipping' stuff.

anyone who does you a personal service

Waiters don't work for me- they work for the restaurant. They are providing service to me as part of their job at the restaurant. Therefore, they should get paid by... the restaurant, and not directly by me.

All 'tipping' does is allow restaurants to pay their employees less and make more profits.

Re:Mark Newman Poster

[ConceptJunkie]

It's not the wind. It is the earth rotating under the rocks. Not sure of the latitude of the location but the earth is rotating at something around 1000 miles per hour at the equator.

Well, you know of course that why the famous experiment with marbles on a smooth surface works. It's well known that any object on a relatively frictionless surface will slowly drift to the West because of the Earth's rotation. This is why that old design for "air hockey" was unfeasible. That's why marbles on balanced glass always roll Westward. It's how compasses work.

That's also why ice rinks nearer the equator need to be tilted slightly to compensate for the effects of the Earth rotating from under the skaters. I understand that an ice rink built in Quito in 2004 had to be slanted at nearly 7 degrees.

I understand that the government of Indonesia is building a 7 mile long maglev runway that will allow airplanes to be launched at almost 400 miles per hour (wind resistance cuts it down from the full 1000), merely by placing the airplane on the track and letting the Earth's rotation fling it into the air. At that point the engines cut in. The system is expected to cut fuel costs for air travel by almost 30%.

This same effect is what powers that "perpetual motion" turbine that generates power for the Amundsen-Scott South Pole Research Station.

Re:Mark Newman Poster

[bruce_garrett]

I have a question. How did these fairly heavy looking rocks come to rest not just in, but On the surface of this dried up lake bed in the first place? The nearest edge of this lake bed looks pretty far away in the photos I've seen of these moving rocks, so it's hard to believe they tumbled down the sides of those mountains to rest there. The satellite view makes me wonder even more. That's a pretty big lake bed.

Re:Mark Newman Poster

[_anomaly_]

Good call...

(and it is)

Re:Mark Newman Poster

[Skreems]

In the first case, you'll probably find that the person wasn't notified beforehand. If they inform you beforehand of a charge associated with dining at their restaurant, and you sit down, order, and eat, you're entering into a contract with them. The law takes a dim view of springing unusual clauses of a contract on someone after the fact, which is why they need to inform you beforehand. But provided they do so, it's no longer optional. And in fact, they've told you it's not optional. You can't ignore the one clause of the agreement just because you don't consent to it. Your option is to choose to eat there, or not.

Re:Mark Newman Poster

[Linux_Bastard]

What is happening there is that the cohesive water is acting as a flexible seal around the bottom of your glass, and it is resting on a cushion of trapped air.

When the glass is put down, if the water seal forms before the glass has fully contacted the surface, the air pressure will lift the glass as it evens out the pressure on the air cushion. This will cause it to be riding on an air bearing, and slide very easily.

Usually it will only go until the water seal is broken, releasing the air pressure that forms the cushion. If the surface is moist enough, the cohesive water can renew the seal as it glides.

If you try this with a very flat, nearly level surface and a glass with a concave bottom you can get good results.
Hot liquids can actually expand the air under them and suddenly lift up and slide.

Re:Mark Newman Poster

[Phoenix Rising]

Been out there photographing, and I did find a couple of rocks that had obvious signs of people moving them, mostly toward the edge of the playa. But there's no way someone got to all of the rocks that had been moved without leaving signs - too many rocks, scattered across too much territory, and if the rocks left tracks, so would anything else.

Re:Mark Newman Poster

[thejuggler]

Now that is a most brilliant idea. And make sure you have a GPS locater on board in case the darn thing does move.

Re:Mark Newman Poster

[Anonymous Coward]

I guess Europeans assume the tip is included in the bill. In the U.S. people are expected to survive on tips.

Re:Mark Newman Poster

[Anonymous Coward]

If you've got GPS you can log when it actually moves. Then cross reference with the weather at that time. Maybe it should include a weather station too.

It's a Horta!

[loftwyr]

I saw this on TV once! It was this documentary about these very things! They're called Hortas and their intelligent. Apparently they can be taught to mine.

Re:It's a Horta!

[iggymanz]

you also don't want a female Horta to sit on your face if you wear glasses, that hydrofluoric acid they secrete when they're horny eats right through spectacles.

Re:It's a Horta!

[Borgschulze]

If makes a Sparta reference, I'll throw 13 chairs at them.

Re:It's a Horta!

[blueturffan]

No Kill I

Re:It's a Horta!

[sokoban]

Yes, and though the flow of water surrounding these things can be directed, these Horta do not readily absorb moisture.

Thus, you can lead a Horta water, but you can't make it drink.

Re:It's a Horta!

[Anonymous Coward]

Oh. So the movements of the rocks have to do with Horta culture.

You know, TFA mentions they experimented with stakes to test the "ice sheet" theory. I have an idea.

Instead of testing individual theories by leaving stakes sitting around, how about getting a definite answer by leaving a webcam?

Re:It's a Horta!

[wximagery95]

I'm actually surprised someone hasn't used techniques similiar to what the photographers of the Planet Earth series did to get some of their exceptional time-series shots. Plant a camera out there for a year, take a snapshot every minute (or use motion detection), collect weather data (humidity, dew point, temperature, evaportion rates, wind speed/dir) and corrolate that to the time-series snap shots.

For the Planet Earth series, scientists sat on the Antarctica continent for a full year. They also perched themsevles in a tree house in a tropical rain forest for more than 8 weeks.

Re:It's a Horta!

[Anonymous Coward]

They're called Hortas and their intelligent. Apparently they can be taught to mine.

But apparently not to spell.

Re:It's a Horta!

[ptbarnett]

I'm a doctor, not a bricklayer!

Re:It's a Horta!

[GeekZilla]

"Instead of testing individual theories by leaving stakes sitting around, how about getting a definite answer by leaving a webcam?"

THANK YOU! Oh my god! And these are actually "scientists" studying these things? Sure, maybe hooking up to the internet is a little dicey in Death Valley, but there are other ways. They need some college kid hyped up on caffeine to wire together a solar-powered, weather proof DVR and finally solve this mystery. I mean, come on! How long have we known about these tracks? Decades?

Sorry, I tend to get a little touchy when there is a mystery and 1) the experiment that could solve it is REALLY simple and 2) The mystery has been around for years. I think it would make a good thesis...no, I think it would make a decent term paper for some high-school senior interested in Geology.

Re:It's a Horta!

[camperdave]

Plant a camera out there for a year, take a snapshot every minute (or use motion detection), collect weather data (humidity, dew point, temperature, evaportion rates, wind speed/dir) and corrolate that to the time-series snap shots.

... and hopefully you'll be able to find out who made off with your expensive camera.

Re:It's a Horta!

[porkchop_d_clown]

They've tried. The rocks apparently do not move very often - which reinforces the rain theory. Rains come rarely, but when they come they tend to be real wind storms - so no witnesses. By the next day, the mud has dried out again.

Re:It's a Horta!

[fitten]

Also... it's evidently a fairly large area with a sparse population of sliding rocks... how many cameras and instrument packs do you need for full coverage to a reasonable resolution? How many to have reasonable coverage enough to perhaps capture one moving and the conditions during which it moves?

Re:It's a Horta!

[hal9000(jr)]

I'm actually surprised someone hasn't used techniques similiar to what the photographers of the Planet Earth series did to get some of their exceptional time-series shots. Plant a camera out there for a year, take a snapshot every minute (or use motion detection), collect weather data (humidity, dew point, temperature, evaportion rates, wind speed/dir) and corrolate that to the time-series snap shots.

It's a national park or preservation or something like that. Basically, you can't (legally) put anything permanent out there.

Re:It's a Horta!

[xSauronx]

Sit on my face, and tell me tha--- Oh god my eyes... THE BURNING! it burns so bad!

Re:It's a Horta!

[Carnildo]

There are a number of reasons why they haven't:
* The rocks don't move very often -- typically once every two or three years.
* Cheap webcams have only been around for a few years, and I don't know if there have been any movement episodes during this time.
* It's an incredibly hostile environment for electronic equipment: surface temperatures of 150+ degrees F during summer days, temperatures below zero F during winter nights, violent rainstorms, and intense direct sunlight.
* There is no electricity. There is no internet service. There is no wireless phone service. During the rainstorms when the rocks are expected to be moving, there is no satellite service.
* There's the ever-present risk of theft.

Re:It's a Horta!

[jfdawes]

.... the goggles ... they do nothing ....

Re:It's a Horta!

[martinX]

They won't move if they know they're being watched.

Re:It's a Horta!

[Carnildo]

Sure, maybe hooking up to the internet is a little dicey in Death Valley, but there are other ways.

"A little dicey" is an understatement. Racetrack Playa is about as middle-of-nowhere as you can get in the lower 48. At a first guess, you'd need to run about a hundred miles of wire over the tallest mountain range outside of Alaska to get an internet connection there.

They need some college kid hyped up on caffeine to wire together a solar-powered

Armored against hailstorms, I presume?

, weather proof

An operating temperature range of -25F to +175F should cover what you need -- this will be sitting in direct sunlight, and it gets damn hot at times. Not exactly off-the-shelf equipment.

DVR

If it's going to be unattended, you'll need a minimum of a few months' video storage. The rocks don't move very often.

1) the experiment that could solve it is REALLY simple and 2) The mystery has been around for years.

It's conceptually simple, but the engineering details are a nightmare. The small, cheap webcam is an invention of the past few years, as is cheap high-volume storage. The experiment could not have been performed on a university budget more than about five years ago: before that, you'd need to pay someone to live out there full-time, swapping videotapes every six hours. The rocks only move once every few years, so even if they've got a camera out there now, it's possible that the rocks have't performed.

Re:It's a Horta!

[hazem]

Easy! You just put a camera to watch the camera...

I wonder if they can just "tag" the rocks like they do with sharks, elephants, walruses, etc. I mean, I know the rocks don't have ears or collars, but there has to be a way.

Re:It's a Horta!

[dfn_deux]

The Horta culture is really complex like that ;)

Re:It's a Horta!

[Torvaun]

Satellite internet connection providing streaming video to off-site storage. Oh, and it's in a shaded booth, to keep off the direct sun and a lot of the heat. I like solar for the power, but I could see someone putting a diesel generator there instead. We could probably use wind power too, if it's really fierce enough to move boulders.

Re:It's a Horta!

[jamstar7]

So many great setups, so few modpoints.

Re:It's a Horta!

[Anonymous Coward]

The answer is in TFA:

The climate in this area is arid. It rains just a couple of inches per year. However, when it rains, the steep mountains which surround Racetrack Playa produce a large amount of runoff that converts the playa floor into a broad shallow lake.

There you go: you have the source of the rocks (nearby mountains), the force that pushes the rocks (water: much more plausible than the wind), explanation for parallel tracks. I only wonder where're the IT angle in this.

If stones that move are a mystery, how about stones that grow a few millimeters a year (just images, no English text) ?

Re:It's a Horta!

[NewsWatcher]

"surface temperatures of 150+ degrees F during summer days"
Your post loses much credibility when you pluck ridiculous figures out of the air and use them to make an argument.

Given the hottest temperature ever recorded in the United States is 56.7 degrees celsius (134.1 degrees fahrenheit) I find it impossible to believe this small part of America regularly gets temperatures of above 65.6 degrees celsius (150F).

As an aside I find it not so amazing that these rocks move about, but that similar phenomenon doesn't seem to happen elsewhere in deserts where you get similar extremes of temperatures, rock types, and often windy weather. Let's hope Google earth kicks into action and someone observes this phenomenon soon.

Re:It's a Horta!

[vought]

Given the hottest temperature ever recorded in the United States is 56.7 degrees celsius (134.1 degrees fahrenheit) I find it impossible to believe this small part of America regularly gets temperatures of above 65.6 degrees celsius (150F). A friendly nitpick: surface temperatures on the desert floor - even on light-colored surfaces like the Racetrack - can often rise above 200 degrees F. Note that the ambient temperature may be far cooler than the ground surface.

From a dependable source:

In the heat of summer, Death Valley roasts in temperatures greater than 120 degrees, cool when compared with the surface temperature of the salt pan. "The ground temperature gets to over 200 degrees [f] at some points here," says Dr. Douglas. I'd wager that the surface temperatures at the Racetrack in early afternoon during high summer range above the boiling point of water at sea level*, since the racetrack's playa is lower and darker than the salt pan at Badwater. In other words, don't fall; you'll skin and burn your knees.

If you've never been to Death Valley in the summer, you should give it a try. If you're from a mild climate, I suggest March instead; the regular 90 degree temperatures before April has shown it's face will give you a little idea of the radical heat that this region experiences.

*The Racetrack and Badwater are both below sea level, so you'd need to get up to at least 240f to boil water.

Re:It's a Horta!

[vought]

Whoops, my bad - the Racetrack is at 1130m, while Badwater is below sea level.

Re:It's a Horta!

[Walkingshark]

Why not grab a 3m x 3m x 10cm sample of the surface, take it to a lab, hose it down, drop a rock on it, and turn on a fan?

Re:It's a Horta!

[Tablizer]

I saw this on TV once! It was this documentary about these very things! They're called Hortas and their intelligent. Apparently they can be taught to mine.

Another orig-series episode that's fitting is the one where there were beings who moved at a speed so fast that the regular crew could not see them. Maybe the rocks are the slow form of life. If you speed it up, you'd see them doing things, going places, and talking to each other.

Maybe they're plotting against us humans.

Re:It's a Horta!

[Sanat]

Sorry, just used my last mod point. i usually hold one in reserve for cases like this.

Re:It's a Horta!

[Sanat]

spooky, some of those rocks looked real

Re:It's a Horta!

[Sanat]

You may have stumbled on to something. Perhaps it is steam that pushes the rock upwards and reduces the apparent weight so that the wind can push nearly a weightless object. A magic combination of temperature and wind. Good thinking!

Re:It's a Horta!

[KORfan]

Install a GPS receiver connected to a data collection platform with GOES radio transmitter. Instrumentation would cost you under $5K. Record the locations of the rocks in time series data. If they only move when it's windy after rainstorms, that's a good clue. If they move when it doesn't rain, that's another clue. If they don't move, and then move at 60 mph, that means you've got a theft problem.

Re:It's a Horta!

[scotch]

I love it when someone chastises another for stupidity and ends up showing their own stupidity! How did you miss the word "surface" in the GP post?

Re:It's a Horta!

[edward2020]

Also, we don't require a complete video history, only the video of movement.

Re:It's a Horta!

[Torvaun]

True, but I assumed that we'd get lots of extraneous movement from buzzards and lizards and shadows and the like. There's probably a partial fix at least, but I'm not planning on actually implementing this thing.

Re:It's a Horta!

[edward2020]

We ought to just leave it alone. It's probably a group of people, former Free Masons and members of the Hermatic Order of the Golden Dawn no doubt, who arrange these rocks as symbols that then influence, I don't know, the stock market or elections. And, you don't see their footprints because they drag them and then walk away in snow shoes :)

I know this sounds unreasonable and a bit quacky. But really, when we've exhausted science and reason, might not we then look to the supernatural. I mean, come one, it's called "Death Valley." Queue the spooky music. I'm getting a sympathetic response from my power crystal just now. Oh GOD! There coming through the door...

Re:It's a Horta!

[iainl]

One camera actually pointed at an existing rock would suffice for a first estimate, I'd have thought. The area is huge, but the rocks don't just run off while you're setting the cameras up.

Re:It's a Horta!

[StuckInSyrup]

Something like air hockey?

Re:It's a Horta!

[porkchop_d_clown]

I think you're wildly under estimating how much work has actually been done.

http://en.wikipedia.org/wiki/Sailing_stones

Bob Sharp and Dwight Carey started a Racetrack stone movement monitoring program in May of 1972. Eventually thirty stones with fresh tracks were labeled and stakes were used to mark their locations. Each stone was given a name and changes in the stones' position were recorded over a seven year period.

Re:It's a Horta!

[iainl]

True, but I was really just trying to counter the claim that you would need to watch the entire area with webcams to gather info. Just watching the area around a chosen rock for a long enough period to catch it moving would do the job.

Sharp and Carey were tracking the movements of rocks at regular intervals, but they didn't see them in the process of moving - otherwise we'd know the conditions that cause it.

Still, we do know that they move in winter not summer, so that's bringing the monitoring requirements down further.

Re:It's a Horta!

[Sanat]

Exactly... a cushion of air that helps to float the stone just like in air hockey. Thanks for the link.

Re:It's a Horta!

[rbanffy]

I wouldn't try to record video.

I would tag the rocks with solar-powered transmitters, deploy a couple solar-powered weather stations around and track their relative positions from a heavier anchored station that could, once a day, relay data on rock and station positions and weather conditions. That way very little data would have to be stored and the devices could be very, very rugged. If data storage becomes a problem, you could even record data at a very slow pace and kick collection into high gear only when interesting things are happening.

As for the rock tracking, I would go either with a minimalistic RFID tag based mechanism (measuring signal strength on many stations to get positioning info) or instrument pack with small (but precise enough) GPS, compass, transmitter and a solar-charged battery. Oh. And, BTW, I would bring my own rocks so I could experiment with shape and other characteristics.

Sounds expensive but not particularly complex. It must be quite doable.

And, even if no tagged rocks move, there would be an interesting record of weather patterns.

Not a bad idea at all.

Re:It's a Horta!

[Dareth]

First thing that came to mind when I read your post:

PAAAAIIIINNNNN!!!!

Re:It's a Horta!

[Reziac]

You're conflating air temperature (regularly above 120F in Death Valley) and temperature of the ground surface, which can be significantly higher than the air temp. Here in the SoCal desert, I've personally seen concrete get so hot that even when hosed down (not just dripped on), all the water steams away in seconds, and I've seen demos of eggs being fried on the sidewalk (required temp: about 165F).

As to the lakebed surface, the clay breaks down into a fine dust that is slippery even when dry, rather like talcum powder.

It looks to me like the movement takes place when the surface is dry; otherwise surface cracks (caused by the flooding/drying cycles) would have reformed *behind* the rocks.

Re:It's a Horta!

[dfn_deux]

The problem I see with your plan is this... We already know that the rocks move, does this actually answer the "how" question?

Re:It's a Horta!

[jafac]

Yes, with sulfuric acid for blood; do as you oughta, add acid-to-watah. . .

Re:It's a Horta!

[Anonymous Coward]

... and hopefully you'll be able to find out who made off with your expensive camera.

Half the posts in this thread are saying how difficult this place is to get to and/or survive in, and the other half (like yours) are saying that any cameras left behind will get stolen immediately.

Obvious Answer!!

[explosivejared]

Anyone who has seen an M Night Shamylan movie or been involved in a Usenet discussion about UFO's can readily see that there is one glaringly obvious answer...

IT'S ALIENS GUYS!! RUN FOR YOUR LIVES!!

Re:Obvious Answer!!

[liquiddark]

I for one welcome our rock-moving overlords.

Re:Obvious Answer!!

[MrAndrews]

That's exactly right! But this year, Earth lost the Curling Galactic Cup because some fool went and fiddled with the game pieces mid-match...

Re:Obvious Answer!!

[jgarra23]

Anyone who has seen an M Night Shamylan movie or been involved in a Usenet discussion about UFO's can readily see that there is one glaringly obvious answer...

IT'S ALIENS GUYS!! RUN FOR YOUR LIVES!!

It's not aliens. It's the new M N Shamylan/Al Gore movie, An Inconvenient Truth II. The rocks are us, we're dead and the desert is NYC in which we think the year is 2100 but really it's 5 billion years ago.

Re:Obvious Answer!!

[dgbrownnt]

But aren't aliens deathly allergic to contact with water?

Re:Obvious Answer!!

[PachmanP]

Which is why they hang out in Death Valley!

I also think the aliens listen to Blue Oyster Cult.

Re:Obvious Answer!!

[kcbanner]

They are actually moving the earth, the rocks just stay still.

Complimentary headline

[Anonymous Coward]

Sliding Cocks Bemuse Slashdotters

News at 11!

Re:Complimentary headline

[Anonymous Coward]

Sliding Cocks Bemuse Slashdotters

News at 11! God damn it, which one of you leaked that vid of me and this guy's mom to the press?

So this is...

[Anonymous Coward]

...nature's version of desert curling?

Re:So this is...

[TimothyDavis]

Is there any other kind of desert curling? Is it listed in OSQ?

Re:So this is...

[Dr. Cody]

Of course not, curling is a crime against nature.

Re:So this is...

[Anonymous Coward]

Yes, but faster-paced and more exciting.

Re:So this is...

[ralfg33k]

...or maybe it's a sign that we have illegal immigration from our northern border? Just don't call 'em "back-baconbacks", eh!

Any word on magnetic influence?

[inject_hotmail.com]

I'd guess it isn't wind...are these rocks ferrous? Or...maybe the earth is tilting on its side...weird stuff like that always happens here...I think our perspective of it is just off a bit.

Re:Any word on magnetic influence?

[stoolpigeon]

has anyone checked the mitichlorian levels in the area?

Re:Any word on magnetic influence?

[$RANDOMLUSER]

Actually, it's caused by the continential tilt. It causes all the loose cannons and nuts and bolts to roll towards California.

Re:Any word on magnetic influence?

[TempeNerd]

Obviously, the rocks were casually lurking on Slashdot, when they read "Move along, nothing to see here..."

{rimshot}

Re:Any word on magnetic influence?

[orclevegam]

Actually, it's caused by the continential tilt. It causes all the loose cannons and nuts and bolts to roll towards California. Well, the nuts at any rate.

Re:Any word on magnetic influence?

[Anonymous Coward]

Obviously, the rocks were casually lurking on Slashdot, when they read "Move along, nothing to see here..." Either that or they clicked on the goatse.cx link...

Re:Any word on magnetic influence?

[melikamp]

And various loose fruits and flakes.

Re:Any word on magnetic influence?

[Anonymous Coward]

They are migratory. Like coconuts. Perhaps two swallows could have pushed one.

Re:Any word on magnetic influence?

[Anonymous Coward]

Troll? Well, I was going for funny, but ok. Think I'll post this one AC, seeing as it's likely to get moded offtopic and/or troll as well (or overrated, I seem to get that one a lot).

I think

[0racle]

I think that I can safely speak for everyone here when I say, 'WTF?'

Re:I think

[Anonymous Coward]

The most compelling theory is that the rocks are made mobile by the extremely rare combination of water, cold weather and wind. A thin ice layer can lift the rocks and provide a slick surface on which to travel.

Answer on page 42 ...

[foobsr]

... literally:
Quote: "Research of the Racetrack has continued. In the April 1997 GPS World, Paula Messina, Phil Stoffer and Keith C. Clarke reported a GPS study they conducted of the Racetrack. In ten days of intense field work they mapped every featured of the playa using differential GPS to produce, "the first-ever, complete, georeferenced, submeter-resolution map of the wandering rocks." (Messina, 1997, p. 42)"
http://sophia.smith.edu/~lfletche/deathvalley.html

But it seems they have no real conclusion too.

What about 'The Force"?

CC.

Re:Answer on page 42 ...

[orclevegam]

GAH! MY EYES!!! Put a warning on that link, geez.

Re:Answer on page 42 ...

[Threni]

Perhaps the stones are moving to escape websites which employ pink text on a purple background?

Re:Answer on page 42 ...

[Kimos]

I didn't really notice the offensiveness of that website. Guess it's one of the rare occasions where I'm happy to be colorblind.

Re:Answer on page 42 ...

[choongiri]

What? Barney the Dinosaur got a job as a research assistant?

Re:Answer on page 42 ...

[foobsr]

GAH! MY EYES!!! Put a warning on that link, geez.

Pfff ...

Real candidates here and WARNING! here!

CC.

Re:Answer on page 42 ...

[orclevegam]

Strangely enough, although both of those are hideous and difficult to read (or stomach as in the second one), they don't have that instant migraine inducing behavior of the previous link. Something about the contrast of pink on purple just makes me want to gauge my eyes out, where as the rainbow flashing seizure inducing second link just makes me want to slap the shit out of it's author and make him take remedial web design courses.

Re:Answer on page 42 ...

[Anonymous Coward]

And this is why Opera lets you, the viewer, change how the page is displayed...

Re:Answer on page 42 ...

[Anonymous Coward]

Brother, after seeing that site, I can assure you that you won't be alone for long.

I mean, goatse is gross and everything, but goatse never made my eyes water and hurt (well, possibly excepting my first goatse exposure).

Re:Answer on page 42 ...

[Anonymous Coward]

And this is why Opera lets you, the viewer, change how the page is displayed...

Exactly. Moved my mouse cursor to the top bar, clicked "author mode" icon and viola - retinal overload to soothing black text on a white background in 1/4 second. One of the 100 or so reasons why I use Opera.

Re:Answer on page 42 ...

[Mariner28]

"gauge my eyes out"? See reference to "teutonic plate" theory above. You were dwarfed by a master there, bud!

Re:Answer on page 42 ...

[E 99]

They conclude that ice isn't involved, which I agree with. I also think water is clearly not involved, since the tracks are disturbing the drying pattern. If the track was originally in mud, it wouldn't look like that.

When conditions are right, very dry sand can flow like a drift of snow on a mountain side. It happens in desert dunes all the time. I think when the conditions are right, the thin sand layers become able to slide over one another, and the wind can slowly move these things under the low-friction conditions.

Re:Answer on page 42 ...

[Anonymous Coward]

Oh my goodness, the design and colors of that site are not good; surely this is a first for the internet, as I have never seen anything but stellar web design before.

RIP Good Web Design, 27 Nov., 2007.

Re:Answer on page 42 ...

[bl8n8r]

> But it seems they have no real conclusion too.

In 1976 they stated, "It is concluded that wind moves the stones when conditions are just right, that this normally happens at least every one to three years on Racetrack Playa, and that ice sheets are not necessary." (Sharp and Carey, 1976).

Re:Answer on page 42 ...

[NeilTheStupidHead]

No, he's going to remove his eyes with wire sized according to the AWG standard.

Begs the question

[orclevegam]

This begs the question, why hasn't someone setup a webcam to record these rock movements and solve this thing once and for all? I mean, if they can setup cameras in the arctic circle, death valley shouldn't be that hard to handle.

Re:Begs the question

[Anonymous Coward]

in before some fag explains "begging the question"

Re:Begs the question

[Anonymous Coward]

Same as "tea begging".

Re:Begs the question

[smooth wombat]

why hasn't someone setup a webcam to record these rock movements and solve this thing once and for all?

The reason is because there is no way to know when these rocks, or which rocks, will move. Since we don't currently know what causes them to move, there is no way to wait for those conditions and then start filming. Even with the best guess (wind + water or ice) you'd still have the multi-choice selection of subjects to choose from.

What would have to be done is to have multiple cameras pointing at multiple rocks waiting for something to happen. It could take days, months or years for these things to move.

Yes, it would be nice to know what causes these things to move but having all that equipment outside for years is just begging someone to steal it.

Re:Begs the question

[Maint_Pgmr_3]

I agree, if "they" [USGS] can put spiders on MT ST Helens to see how the dome is growing and moving, you would think that someone could tape a small GPS on the rock. Duct tape shouldn't change the movement by much.

better yet, put a small weather station, ala north pole, on a sled and leave it in the middle of the playa and see what the weather conditions are and when it moves. 12 volt battery and an automotive condenser should discourage people from disturbing the sled.

Re:Begs the question

[Target Drone]

This begs the question, why hasn't someone setup a webcam to record these rock movements and solve this thing once and for all?

Why not just take some water and a fan up to there to test the leading theory. Wet down a patch of ground to get it nice an slippery and then turn on the fan to see if you can blow a rock around. If that fails then go with the webcam.

Re:Begs the question

[Bob(TM)]

Yeah, but ... how you gonna keep the webcam from sliding? :)

Re:Begs the question

[orclevegam]

Well, I figured it would probably take a year or so of monitoring before you got lucky enough to catch one in the cameras viewing angle, which is why I was thinking webcams that you could just leave there year around. As for stealing it, maybe an enclosure? Plus, I mean, it's a webcam, if someone tries to steal it at least you'll be able to get a recording of them doing it.

Re:Begs the question

[mdielmann]

Yeah, but ... how you gonna keep the webcam from sliding? :) First you take a stick and pound it into the ground. Then you attach a camera to it.
If necessary, a traffic light can be added to increase accuracy.

Re:Begs the question

[smooth wombat]

if someone tries to steal it at least you'll be able to get a recording of them doing it.

Not if they come up from behind it or wear a mask. Trust me, if there is something to be stolen, someone will figure a way to do it. Take a look at the houses in Detroit (and other places) which are up for foreclosure. People are stealing the siding off of them to be sold as scrap.

Re:Begs the question

[onchiman]

It would be easier to look for a big pile of rocks at the opposite end of the lake bed. Wouldn't they eventually all "blow" to the same spot like so many autumn leaves? If the wind can move these things then whenever you get your 4X4 stuck in the mud just wait a while for the wind to blow it out!

Re:Begs the question

[fbjon]

It still seems strange. The place is really dry, meaning there's lots of sun. Just make a small package with a GPS receiver, some simple weather instruments, a radio uplink to a nearby relay, a small camera and a solar panel with battery. If the GPS detects any movement, or the weather instruments detect any drastic changes, turn on all other stuff and start piping data to the relay, which passes it on by whatever means.

If anybody steals the package, it'll sound an alert and record who took it, and where they're taking it.

Re:Begs the question

[Anonymous Coward]

There are lots of ways to investigate this phenomenon.

If you're trying to see if the movement is due to wind, you set up wind instruments that turn the webcams on when the wind blows hard.

You can also attach some kind of GPS reporting system to a moveable rock that calls home when it begins to move, and turns on the cameras at the same time.

Flowing water can generate more force than wind. I would suggest that the rocks may be more susceptible to being moved when the wind is blowing hard enough to get the water helping to first free the rock, then push against it. I'd guess that a shallow water depth may provide the right conditions - with a very strong wind, water will be able build up behind the rock and sweep it along. A shallow depth could even help create a hydroplane condition.

Re:Begs the question

[orclevegam]

If the wind can move these things then whenever you get your 4X4 stuck in the mud just wait a while for the wind to blow it out!

Well, that's a slightly different situation. The conditions here are a very thin layer of mud on top of hard packed dry ground, conditions you'd be hard pressed to get a 4x4 stuck in in the first place. To get a 4x4 stuck you need a relatively deep section of mud as well as a not insignificant portion of the tires to be submerged in it. The conditions out there are closer to those experienced when you hit a patch of oil on a wet road, and as anyone that's done so can tell you, it becomes all too easy to slide your vehicle in those conditions.

As for looking for a big patch of them that might work, but it seems as if they don't all move in exactly the same direction, it's more of a random movement pattern. I believe there's also mountains surrounding this area, so it would be difficult to separate rocks blown to the base of the mountains from those that fell there off the mountains.

Re:Begs the question

[jr01945]

It's wind and the rocks are volcanic. I've been to other dry lakes and seen the tracks and the rocks. It is not exclusive to Ractrack Playa. I've seen these "wandering rocks" on Ivanpah, Silver, and El Mirage Dry lakes. When the playa gets wet, it turns into a sludge that serves as a lubricant. Since the rocks are light and the winds strong, they move. They only leave tracks when conditions are right. I've also seen rocks that just have a bit of mud dried all around them.

Re:Begs the question

[amRadioHed]

Sounds like an episode of Mythbusters to me

Re:Begs the question

[orclevegam]

Dear AC: http://idioms.thefreedictionary.com/begged+the+question STFU.

Re:Begs the question

[evanbd]

Some of us prefer our linguistics to be prescriptive rather than wimpy. Clear usage of terms aids communication, and the fact that more and more idiots are misusing the phrase doesn't make you look like less of one when you willing join the herd.

Re:Begs the question

[PortHaven]

Or mounted a GPS on the a few of the rocks along with a camera. Movement recorded by the GPS would trigger the camera. Relay a signal that the rock is moving...informing scientists to come out and watch the rock move.

Then, we'd finally have some new sound for the record labels to market. Instead of the same ol' same ol rock'n'roll, we'd be able to actually record a new style rock'n'slide baby!

Re:Begs the question

[Torontoman]

Wet down the ground - give one of the rocks a bit of a shove and see what happens. In fact the concept is the same as why curling rocks slide - the ice is actually 'pebbled' in a similar fashion as the cracked mud in these pics.

Re:Begs the question

[gmby]

Or maybe embed a GPS unit in the the rock with some concrete and record the data. Date, Time and directron of travel can be conpaired to rain and wind data for the area.

Re:Begs the question

[owlstead]

Or a big fan and a truck full of water. Or dig up some silt and a stone and recreate it somewhere else, depending on which is easier.

And check if there are no hidden crevices, maybe the rocks contain robotic kites.

Darn, there I go again, both an interesting post and a funny one combined. Consider this two posts.

Re:Begs the question

[Random Destruction]

I'm siding with Paul Brians on this one.
http://wsu.edu/~brians/errors/begs.html

Raises the question != Begs the question.

Re:Begs the question

[PortHaven]

Makes you wonder if the rocks would go faster with KY jelly or the latest most slippery lubicrant of love.

Re:Begs the question

[F1re]

KY Jelly is not a lubricant of love. It's terrible at that as it dries out too quickly. It's designed for medical use.

Re:Begs the question

[Anonymous Coward]

Except...what if your equipment starts wandering around?

Re:Begs the question

[Buelldozer]

Put a heavy rock on the base. That should hold it!

Re:Begs the question

[lindseyp]

>The reason is because there is no way to know when these rocks, or which rocks, will move.

Then set up a motion sensing apparatus. Duh! ;)

Seriously.. you could set up some solar powered motion-sensing equipment *on* a few of the rocks with panoramic cameras and have them record little movies of what was happening whilst the rocks were moving.

Re:Begs the question

[orclevegam]

In this case however it's not being used to describe a piece of formal logic, it's being used as a idiom common in English. Like it or not languages are evolved through common usage, not through design, and even though modern English recognizes certain formal rules, idioms, expressions, and colloquialisms are largely exempt from such rules. My usage of the idiom "begs the question" is perfectly valid and is used in this case to mean roughly the same as "raises the question".

Re:Begs the question

[Dolmangar]

Cheaper solution = Interns

The assignment goes something like this:

"If you want to graduate, you're going to sit here and watch this rock for the next four months. See you in June."

Re:Begs the question

[preem]

Probably noone used webcam before is due to fact its in the middle of the f00king desert :p no internet access there. But one could set up a recording system though and put it on tape, i agree on that one. But, i still think its the aliens... its gotta be the aliens, just like the crop fields, and spagetti monster and stuff.

Re:Begs the question

[Random Destruction]

It's sad you were modded offtopic for this discussion while I got informative, just because the mods agree with me. Either way, I still contest that this usage is incorrect. It may be gaining acceptance, but it still makes one sound uneducated. This usage has no benefits over 'begs the question' and just confuses the issue. Obviously this is not a big deal, but why not just use the actually-correct phrase instead of the gaining-acceptance-but-often-seen-as-incorrect phrase. Or perhaps writing phrases like the previous one disqualifies me from this debate. Oh well.

Why did the rock cross the lake bed?

[Brothernone]

... to get to the sex and drugs on the other side!

Isn't it obvious yet?

[CitznFish]

These stones don't want to gather any moss.

Re:Isn't it obvious yet?

[spun]

While we know that rolling stones gather no moss, more research is needed to determine whether sliding stones do. My hypothesis is that they would in fact gather moss, as the same side is always pointing up. Now I'll just need a $500,000 grant to find out for sure.

Re:Isn't it obvious yet?

[zombie_striptease]

"A rolling stone can gather moss if it is rolling very, very slowly." - Mike Topp

Re:Isn't it obvious yet?

[NeilTheStupidHead]

More importantly, don't build any glass houses near here!

Re:Isn't it obvious yet?

[Anonymous Coward]

Moss has absolutely nothing to do with this phenomenon.

These rocks are very clearly in need of deworming.

Re:Isn't it obvious yet?

[Mariner28]

Submit a SBIR proposal to the Department of the Interior. Check will be in the mail...

The texture of the lake bed where

[iknownuttin]

the rocks have slid still shows. And if these rocks are a few hundred pounds and the texture is still there, then why can't a human walk on it and not have their footprints show?

Re:The texture of the lake bed where

[Brothernone]

Lets ponder this a momment:

Hey bubba, lets finish this whisky and see how far we can push them rocks..

Fun.. but not likely.

Re:The texture of the lake bed where

[An ominous Cow art]

At the time those pictures were taken, the ground had been baked solid. Footprints don't show up well. But when I was there this summer, I did see footprints made when the ground was muddy. There are signs telling you not to walk out there when it's wet - footprints can persist for quite a long time.

Re:The texture of the lake bed where

[StalinsNotDead]

Hey bubba, lets finish this whisky and see how far we can push them rocks..

Fun.. but not likely.

How much experience do you really have with rednecks?

Re:The texture of the lake bed where

[Ambidisastrous]

This has been going on since at least the mid-1970s, so if this is a prank, there are some extremely dedicated rednecks in Death Valley. I bet the area was even named "Racetrack Playa" because of these rocks and the tracks they made, back when it was discovered. The rocks only scoot around once every few years, apparently, but there are a lot of rocks and it looks like they all have trails.

no buildup in front

[egburr]

In all those pictures, I don't see any buildup of dust in front of the rocks, though there is plenty on the sides of the paths. Usually, when I push something through the dirt/mud/snow/whatever, I end up with a good buildup in front, too. I wonder where that has gone.

Re:no buildup in front

[Reality Master 101]

In all those pictures, I don't see any buildup of dust in front of the rocks, though there is plenty on the sides of the paths. Usually, when I push something through the dirt/mud/snow/whatever, I end up with a good buildup in front, too. I wonder where that has gone.

I had to think about this for a second... I think the answer is that if a rock was digging into the mud, you wouldn't have this effect, because of having to shove the mass of the mud. If you look at the pictures, the fronts of a lot of them tend to be sticking up, implying they're "surfing" over the mud.

Re:no buildup in front

[CiRu5]

Well they way I see it, if dirt was to build up in front of these sliding rocks it would create far to much resistance and the wind (or whatever) would never be able to move them. More then likely when the rocks are sliding the are behaving like a boat traveling though water and the trail you see is the "wake". Well that's my take on it anyway.

Cheers

Re:no buildup in front

[Evil Pete]

Yes I noticed too. I also noticed that the rocks pictured were not random shapes. The front of the rocks looking more like a slidable(?) geometry. Perhaps the rocks are not pushing any mud in front of them but riding over it. Too many ifs. We need some observations.

Re:no buildup in front

[Tired and Emotional]

I noticed that too. And if motion was an occasional thing happening only when the mud was soft, would not you see some disturbance in front of the path?

What I would think was an obvious candidate explanation was not even mentioned. That is differential expansion. One would want to model this to check but I can certainly imagine differential expansion of the rocks in the sun causing them to slowly walk.

Re:no buildup in front

[JustinKSU]

The lake is moving around the rock. It's kind of like the spoon thing.

Re:no buildup in front

[Anonymous Coward]

Here's a crazy idea...
It gets damp. (Rain, snow, whatever, etc.) Moisture stays under the rocks while the rest of the area tends to dry out. Then it gets windy. There's fissures and stuff in the ground that let the wind underneath on the windward side. It's also a salt bed. So when the windward side starts to dry, salt crystals form. The crystal formation acts to push the rock until enough moisture under the rock is used up to stop the dissolution and crystalization process.

Plausible? Dunno, but that's my best guess.

Obviously mud

[InvisblePinkUnicorn]

The rocks wouldn't by themselves leave such deep impressions and well-developed ridges along the path unless they were moving through mud.

Re:Obviously mud

[geekoid]

Except this is old and it's a really thin piece of ice.
Because there isn't a place windy enough to push a 100 pound rock through a 1/4 inch of mud. SOmething must be lowering the friction AND be thin enough to break.

Re:Obviously mud

[InvisblePinkUnicorn]

Maybe the ground has a slight tilt.

Re:Obviously mud

[pizpot]

Try to walk up a wet clay riverbank sometime. Clay mud is like Astroglide.

Re:Obviously mud

[Reziac]

Powdered clay is extremely slippery too. Very like talcum powder.

But when this stuff is wet, you can't walk on it at all -- you SINK.

It's pretty clear the trails are made when the surface is dry; if it were wet, then there would be cracks (generated as it dries) behind the rocks, which would quickly obliterate the trails.

Another question: do rocks pile up at the lower end of the lakebed? Seems to me they'd eventually get there.

Magnetism?

[teknopurge]

Do the rocks have a large iron content? I wonder how the magnetic fields are in the area...

Re:Magnetism?

[Threni]

I was thinking magnets, or perhaps the ground isn't completely flat and there are some vibrations shaking it.

Re:Magnetism?

[Rob T Firefly]

Do the rocks have a large iron content? I hope not. If there's one thing I can't stand, it's ironic rock.

Re:Magnetism?

[spun]

Ironic rock is worse than rai-e-ain on your wedding day, or a free-ee ride, when you already paid.

Re:Magnetism?

[wfstanle]

I doubt it. If it was any constant force like a magnetic force field or some gravity effect, all the trails would be straight on all would go in the same direction. From the photos I have seen, some of the trails cross others. Try explaining how trails can cross. It has to be some force that changes over time such as wind.

Re:Magnetism?

[Anonymous Coward]

The only ironic thing about that song is that the author has misunderstood what irony is

Re:Magnetism?

[spun]

The only ironic thing about that song is that the author has misunderstood what irony is. Really? Are you sure she wasn't being... ironic? I mean, what could be more ironic than a song about irony that contains no irony? Wait, that means it does contain irony, so it isn't ironic, but that means... ah, my head!

Grants

[conureman]

Can't one of these bemused scientists think of a military app (this is war, folks) and get a grant to research this. I have always wondered why they hadn't been able to attribute this definitively to the wind, or something.

Re:Grants

[wattrlz]

Ah yes, I can see the grant appliction now, "...it is the delief of this researcher that the technology derivative of this work can be used to slowly nudge insurgents out of the way with massive lithic engines of war..."

Ice Sheet

[liryon]

This is not new, or news worthy. A more accepted theory than the one in the blurb is that the rocks get trapped in large ice sheets which are in turn moved by the wind. This explains why rocks that are very far away move in the same exact patterns. Its in the article, but way to not mention it in the blurb. Its still pretty neat, all in all, obligatory you tube video: http://www.youtube.com/watch?v=u1hoiHvOeGc

Re:Ice Sheet

[mpathetiq]

From TFA:

Some researchers have found highly congruent trails on multiple rocks that strongly support this movement theory. However, the transport of a large ice sheet might be expected to mark the playa surface in other ways - these marks have not been found.

Other researchers experimented with stakes that would be disturbed by ice sheets. The rocks moved without disturbing the stakes. The evidence for ice-sheet transport is not consistent.

Re:Ice Sheet

[Anonymous Coward]

Your obligatory youtube link says that it captures the forces moving the rock for the first time, but it doesn't show any rocks actually MOVING, which makes it a pretty bogus claim.

I am pretty sure ...

[Culture]

... that the rocks slide because the lateral forces exerted on the rocks exceed the static and dynamic frictional force cause by the gravity induced weight of the rock acting across the mud-rock interface. I guess I could be wrong and there are worm-holes involved.

Re:I am pretty sure ...

[Al Al Cool J]

Not necessarily. Some kind of localised microtremor could cause the ground to jolt quickly beneath the rock by a small amount. The rock would stay more or less motionless in the Earth's reference frame, while the ground moves quickly beneath it, its frictional forces unable to overcome the rock's inertia. The ground could then settle back to its original place more slowly, this time taking the rock with it.

Re:I am pretty sure ...

[Burdell]

Those would be some pretty big worms, to be making holes that would move these rocks. Was there a nuclear plant nearby, leaking radiation and creating mutant giant rock-moving worms?

Re:I am pretty sure ...

[reallocate]

Didn't you just say that the rocks move because they are pushed by something strong enough to move them?

Re:I am pretty sure ...

[Culture]

Dude, if you explain these things in simple terms that everyone can understand they will never pay you the big bucks!

Re:I am pretty sure ...

[flux pinner]

Dude, forces are so boring. I'd much rather explain it in terms of energy. Clearly, the rocks slide because the total free energy of the system (rock + ground + atmosphere) at the final position is lower than the total free energy at the initial position. Oh, and there is sufficient perturbative energy in the system to overcome any kinetic barriers that might exist during the state-transition process. That should do it.

god doesn't play dice

[circletimessquare]

but he does hold magnets under the surface of the table, moving objects on top as if by magic, just to bemuse and entertain us

Re:god doesn't play dice

[chubs730]

At least bemused is being used properly somewhere on the internet

One thing I know for sure

[mcg1969]

is that posting this article in Slashdot is sure to produce a definitive solution to the mystery...
or rather, 100 of them.

Re:One thing I know for sure

[Anonymous Coward]

is that posting this article in Slashdot is sure to produce a definitive solution to the mystery...
or rather, 100 of them.

... many of which would suggest implementing various distributions of Linux... still more would simply blame Microsoft and/or Vista... and a small few would have something to do with Natalie Portman...

Re:One thing I know for sure

[Anonymous Coward]

How the rocks slide around:

It does rain there sometimes. When it does, that dry lake bed becomes a real lake (only a few inches deep though). Now, the rain usually coincides with other forces, for example freezing winds often follow (it looks hot out there, but deserts can get cold). The freezing cold air freezes the top of the "lake" so there is a sheet of ice "floating" on top of the lake. The winds are strong, but they don't have to be that strong to move the rocks at this point. The fiction between the wind and the solid surface of the "lake" (the whole surface) adds up to a lot of total force. The layer of ice begins to move, and it can do so because its floating on water. Since ice is a rigid body, a lot of that force can focus on any obstruction. A few rocks are no match for a moving sheet of ice covering a whole lake. Sure the ice will break around the rocks, but they will push them too. The thicker the ice and the faster the wind, the better (but if the ice gets too thick it won't float anymore). Keep in mind, the ice doesn't tumble the rocks, it slides them. Ice can't tumble rocks, but it can slide them over slick muddy surfaces.

And there you have it.

Quick! Alert the creationists!

[Kintar1900]

Obviously, the only way these rocks could move is if God told them to. Finally! Concrete proof of creationism! :)

I for one

[Lucas123]

welcome our new sliding rock overlords, even though it will likely be a very slow conquest.

Re:I for one

[mcmonkey]

Don't hate the playa; hate the game.

Another possibility

[suso]

Maybe this is what moved them.

Not even a webcam.

[khasim]

Take MOVIES of the stupid things ... and have devices in view that measure the wind speed and the temperature.

Also, build a rock with different measuring devices in it and see if IT moves.

Re:Not even a webcam.

[Anonymous Coward]

Take MOVIES of the stupid things

Ah, yes...but would the end result gross more at the box office than a film starring Tom Cruise?

Re:Not even a webcam.

[Torontoman]

Hell- Just duct tape a camera to the dang rock.

Its not that hard to figure out!

[Henneshoe]

If there is really this much interest in figuring out how the rocks move, its pretty easy to do. Mount a solar powered camera with a motion detector. If the rock moves start shooting. If you really want to get fancy, you could do a continual time lapse to catch the movement if it is too slow for the motion detector. I think they do this kinda thing when you want to get pictures of wild animals in there natural habitat and the cameras are avaliable at your nearest outdoor outfitter.

Re:Its not that hard to figure out!

[fahrbot-bot]

Mount a solar powered camera with a motion detector. If the rock moves start shooting.

Logic dictates that they'll then only move at night... :-)

FSM

[Anonymous Coward]

They were obviously moved by his noodly appendages.

Skeptoid

[Myopic]

The Skeptoid podcast addressed this issue and presented a theory. Most theories have the wind pushing the rocks, but that doesn't make much sense since it's hard for wind to push a big rock a long way without rolling. Skeptoid says the lake is sometimes frozen (we're talking about very shallow water here) so there is a layer of ice thru which the rocks protrude. At this point the wind acts on the whole sheet of ice which has the power to slide the rocks without rolling them.

Yeah, that or it's space aliens with magic brainbeams using multidimentional quantum effects.

(PS the Skeptoid podcast is pretty good. Find it on iTunes.)

Re:Skeptoid

[NeilTheStupidHead]

Another theory that I've heard (which isn't mentioned in this article) is that the daily expansion and contraction of these rocks causes them to inch along. No idea how plausible any of these theories are. Until we set up a camera (including one that can take night shots) and record it, we won't know for sure.

Re:Skeptoid

[dargndorp]

And here are the links to the Skeptoid podcast:
The podcast proper: http://skeptoid.com/episodes/4021
The video mentioned in the podcast: http://www.youtube.com/watch?v=u1hoiHvOeGc

Uri Geller

[JBHarris]

Uri Geller got tired of bending spoons. He's been doing this for years out of pure boredom.

Problem solved

[daves]

It rains. Water freezes into large floating sheets. Sheets are blown around. Rocks move.

Re:Problem solved

[shaka999]

Funny, I don't see any evidence of large sheets of ice in the pictures. You'd think they would leave a mark.

I for one...

[popo]

...welcome our new geological overlords.

Re:Quick! Alert the creationists!

[CannedTurkey]

Touche.

Re:Quick! Alert the creationists!

[Anonymous Coward]

Quick! Your a flaming troll atheist.

Silly scientists...

[VE3MTM]

Clearly the Flying Spaghetti Monster is moving them with his Noodly Appendage.

Re:Silly scientists...

[Karl0Erik]

Touché(d).

Re:Silly scientists...

[Quartz25]

Or Zombie Jesus could be moving the rocks from his burial point.

Trolls!

[Ecuador]

Sorry guys, but I personally don't have to see a photo in the far-octarine to tell that these are your average, semi-bored trolls. They will obviously just look like rocks to the untrained eye during daytime, but they are no puzzle to someone who's been around the disc...

Re:Trolls!

[Devistater]

Hahahahaha, nice discworld reference

duh!

[sunking2]

Stupid scientists. It's the Graboids doing it. And Kevin Bacon HAS seen them.

What mystery?

[Kozar_The_Malignant]

From our friend wikipedia we learn: "Professor John Reid led six research students from Hampshire College and the University of Massachusetts in a follow-up study in 1995. They found highly congruent trails from stones that moved in the late 1980s and during the winter of 1992-1993. At least some stones were proved beyond a reasonable doubt to have been moved in ice flows that may be up to half a mile (800 m) wide. Physical evidence included swaths of lineated areas that could only have been created by moving thin sheets of ice. So wind alone as well as in conjunction with ice flows are thought to be motive forces." (References in the article.) Once a mystery, but not really one now.

Re:What mystery?

[sunking2]

Hampshire college. Can we look for an explanation that didn't come about from smoking massive amounts of dope in the middle of the desert.

Re:What mystery?

[Dr. Cody]

Interviewer: So, have you been published?

HampU grad: Yeah, I've submitted three papers to "The Fortean Times."

Re:What mystery?

[jcaplan]

Thanks for mentioning John Reid's contribution to solving this puzzle. I was one of his students a number of years ago.

Professor John Reid was truly a great scientist. He was not the kind who worked solo in the lab late into the night coming up with the brilliant discovery. Rather, he was passionately curious about the world around him. He simply loved to solve puzzles and presented learning about geology with a sense of curiosity and wonder which drew in other curious minds.

As one of his students, I had the pleasure to watch him work on many occasions. He might have a hunch about how a system might work, or more often that just that we might learn something about it. His investigations were quite wide-ranging, though generally in the areas relating to flows of surface waters. The problems he attacked would range from details of the dynamics of river flow, stream chemistry, or mixing of waters. He would gather all kinds of data, often by turning a class of students loose with a variety of equipment for a few hours with a set of tasks. The data would then be distributed to the entire class to analyze and share. The labs had a sense of adventure and exploration. The sense I always got from him was that he always saw many discoveries just waiting to be made. All that had to be done was to think about something for a bit, collect some data and see what it might be telling us. He always seemed to get close and personal with data, to really look at what the numbers might be trying to say, and taught me to do the same. His students were involved with his research in ways that undergraduates rarely are, which was facilitated by Hampshire's system in which students complete a major research project as a condition of graduation.

One of these opportunities to watch him at work was a week long-spring break field trip to Death Valley with John, several professors and about 25 other students from Hampshire College, Amherst College, Mount Holyoke College and the University of Massachusetts in 1992 (or was it 1991?). It was an amazing time to be surrounded by a group of people, both professors and students, who loved geology in a place with such great geological features. We saw many things, one of which was the Racetrack Playa. I remember standing with him at the edge of the playa, explaining the mystery of the skating rocks to us. At that time he had already suspected an ice sheet blown by wind was involved and pointed out the parallel tracks to us. The tracks would go some distance, often in a straight line, then abruptly change direction. He was planning to return in colder weather to test the ice hypothesis, which I remember him reporting that he had verified some months later.

I learned a few years ago of his passing in 2003, but I will never forget the impact he had on the way I thought about science.

Thank you very much John.

- Jon Caplan

Here's an idea:

[urcreepyneighbor]

Solar panels + satellite dish + webcam + weather station + time = possible answer(s).

Playing grab ass in the dark isn't going to bring us any closer to the truth.

Tax Dollars at Work!

[lionchild]

I sense that there are some tax dollars at work, or soon to be at work on this very question! Perhaps we could have the government fund a study to watch these rocks, observe them 24 hours a day, 7 days a week, 365 days a year, record their activity, and uncover the truth! It's for science! ;-)

Amazing how no-one bothers to actually CHECK.

[Rob from RPI]

They just say 'no-one's seen this happen' and 'there's no possible explanation' when 5 seconds worth of googling produces not only a video of it happening, but a foolishly simple explanation too.

http://video.google.com/videoplay?docid=4311978216520105215&q=death+valley

(It's in the video. Water pushes the rocks.)

Re:Amazing how no-one bothers to actually CHECK.

[leehwtsohg]

In the linked video, you see water and foam on top of the water being pushed by wind, not rocks moving, as far as I could tell. The also mention something about vast sheets of ice forming, though no explaination how the ice fit in to the picture. In other words, what I understood was: it has something to do with wind, water, mud, ice, but we don't know exactly how or what.

Re:Amazing how no-one bothers to actually CHECK.

[E 99]

Er, I didn't see any rocks moving in that video. Just some water moving and a guy who says he knows why the rocks move.

Re:Amazing how no-one bothers to actually CHECK.

[Ambiguous Coward]

Come now...while I agree that the video is (mildly) interesting, it is not what you claim. But beside that, the article doesn't say "there's no possible explanation" at all. In fact, the article presents at least a couple possible explanations. In fact, and I say this with every ounce of *gasp* I can muster, the article presents an explanation for the moving rocks that is identical to the one presented in the video! Did you happen to read the article? You ought to. It's relevant to this discussion.

-G

Re:Amazing how no-one bothers to actually CHECK.

[bornwaysouth]

I watched the video. It does show moving water. Then leaps into theory again about ice and things going bump in the night. It adds evidence, but is not conclusive. Most posts seem to quote pre-millenium data, and the emperiments are passive. They observe and do not intervene. With cheap GPS available these days, how about adding some large rocks with GPS and temperature recorders attached to them. I assume that this is a nature reserve where permanently gluing gadgets to local rocks is forbidden. That means importing rocks, and later taking them away. Camoflage the recorders or some local troll will just move the rocks for fun. See if movement occurs when cold. Ideally, wind and rain is being measured as well.

Of course, an intelligent rock knows to move only while a glib explanation is valid, so excellent data never rules out a good conspiracy theory.

Re:Amazing how no-one bothers to actually CHECK.

[DigitalCrackPipe]

In true /. form, you either failed to RTFA or to WTFV, as the video clearly does not show the rocks moving. It shows water and miscelaneous floating scum moving, and posits the same theories as in the article (just claiming them to have been proven).

And as to the foolishly simple explanation, H.L. Mekcken is quoted to have said, "Every complex problem has a solution that is simple, direct, plausible, and wrong".

Re:Amazing how no-one bothers to actually CHECK.

[exp(pi*sqrt(163))]

If only physicists would look for the Higgs particle on google video. It would save a lot of money.

Re:Amazing how no-one bothers to actually CHECK.

[Anonymous Coward]

(1) Find a non-signed non-dated pseudo-scientific article on the web.
(2) Post a slashdot news about the greatest scientific mystery since sliced bread.
(3) ...
(4) Profit!

Re:Amazing how no-one bothers to actually CHECK.

[evanbd]

Did you watch the video carefully? They offer a very authoritative sounding explanation of the water / ice theory presented as one option in the article, but don't actually capture rocks in motion on film. There's water moving, and some sort of foam on top of the water, but that's about it. As the original article says, there's lots of evidence in favor of this theory, but also evidence against it being that simple -- like experiments involving undisturbed stakes and such. As far as I can tell, that seems to be a piece of the explanation, but not the whole explanation.

Re:Amazing how no-one bothers to actually CHECK.

[Anonymous Coward]

I've actually seen that video at a previous business, so...

Re:Amazing how no-one bothers to actually CHECK.

[apemsel]

Sorry for being sceptic, but at least one of the other videos by the same user is an obvious fake ("The Gunsight Mine"). And it still does not show any of the stones actually moving.

Re:Amazing how no-one bothers to actually CHECK.

[JoeInnes]

On the other hand, Occam's Razor says "Entities should not be multiplied beyond necessity". Go figure.

Re:Amazing how no-one bothers to actually CHECK.

[breagerey]

And as to the foolishly simple explanation, H.L. Mekcken is quoted to have said, "Every complex problem has a solution that is simple, direct, plausible, and wrong".
since we're apparently tossing about platitudes, think Occam's Razor
"All things being equal, the simplest solution tends to be the best solution"

Re:Amazing how no-one bothers to actually CHECK.

[Taleron]

The narrator almost sounds like Kevin Murphy. I was so hoping for some commentary!

Re:Amazing how no-one bothers to actually CHECK.

[i*rod]

The phenomenon is not unique to the lake bed in question, neither is it unexplained. I'm surprised S/D devotees haven't cottoned on to the physics. I waited until this morning, expecting to see the explanation appear. The stones don't really move. During heavy storms, the surface becomes a slurry that moves over the firmer, dryer and compacted layer beneath; propelled by the wind that often accompanies storms. The same principle applies to the movement of surface water relative to sub-surface layers of water on lakes and oceans due to wind. The alleged "trail" of the stone can be likened to the apparent "wake" of a boat that is anchored in a current, the conic "comma" on the lee side of an object on a windy sand dune, or the apparent "trail" left by a stone on a silty beach after the tide has gone out.

Answer

[phalse phace]

CowboyNeal

The rocks are stable...

[planckscale]

...it is the earth that is moving underneath them. Perhaps there is enough of a lift by a small mud sheet that the rotational forces of the earth allow the rocks to slide on top.

Re:The rocks are stable...

[ls671]

Nice try but the rocks move (rotate) with the earth surface just like you are. In fact if the earth suddenly stopped to rotate, then the rocks (and yourself) would start to move quite a bit ;-)
Also, if you throw a ball horizontally 500 feet in the air when there is no wind, it will fall on the same spot because even earth atmosphere rotate with it (at least when wind is at 0 ;-)

Vandals

[conureman]

Why is it that when we see something like this, we often want to improve on it? I can remember when I first saw this place, back in the '60s, I wanted to drop a few rocks on the playa and come back later to see if they'd moved.

This is pathetic science

[Anonymous Coward]

Stick a GPS tracker, a few sensors and maybe a webcam with a radio transmitter on a fake rock, and leave it there.

Wait for the fake rock to move.

Is it raining? Then mud is a factor.
Is it windy? Then wind is doing the moving.
Is it cold enough for a sheet of ice to form? Then ice is a factor.

The only reason this is still a mystery is because no-one cares enough about actually solving the mystery to fund the solution. This isn't expensive.

Begs the answer(s)

[tomzyk]

1) funding
2) laziness
3) All of the above (better things to do with current funds and time/effort)

Omni SF short-story

[Cctoide]

Heh. I'm reminded of an old Omni short-story they published in one of their short-story compilations, "The Rocks That Moved". The reason behind their movement was a bit different, though...

Runaway solution

[denominateur]

There's obviously a runaway solution in the differential equation governing that part of the Matrix.

Re:Global Warming

[AlamedaStone]

because teutonic plate theory was just too crazy to accept...
 
... although it replaced the even more silly Gaulish plate theory, quickly discarded by history.

Re:Global Warming

[Anonymous Coward]

I think "teutonic plate theory" would be something to do with German crockery. Do you mean tectonic?

Noodly appendage

[Anonymous Coward]

The invisible flying spaghetti monster is using one of His Noodly Appendages to change the position to confound our scientific measurements, just like he does with carbon dating.

Re:Global Warming

[toddhisattva]

teutonic plate theory Funniest typo this week!

Re:Global Warming

[Maint_Pgmr_3]

roaring extrapolations about global warming

I think they are just trying to cover up the blunder that they made with the 1970 Clean Air Act, which was fixing the errors of the 1967 Clean Air Act.
But that is what happens when you have to make a rapid "tradeoffs" to a problem that you don't understand. Trade HydorCarbons, CO and NOx for H2O and CO2, let's hear it for catalytic converts.

MOD PARENT UP!

[denzacar]

Thank you!

I remember this thing from back in '80s and even back then it was obvious that its water+wind+ice that makes the rocks move.

What is next? Channels on Mars?

One possibilty

[edwardpickman]

I'd be curious if the under sides of the sliding sliding stones were concave? Why I mention it is I still remember a certain chinese restaurant's tea cups had a habit of sliding across the table. The table tops were resin coated and the concave cups tended to capture moisture under them so when the tea heated the moisture under the cup the expansion provided enough lift to break the friction and allow them to slide. They would move randomly in different directions then stop for a few minutes then slide again. Since the area is hot a unique combination of heated rocks with slippery mud and wind could in combination cause the effect. I remember that some rocks slid and others didn't as well as the direction changes.

Re:One possibilty

[eric2hill]

I absolutely agree with you. There used to be a restaurant in town that had "fancy" glasses for drinks. They were fairly thin-walled glass with a nice concave bottom and were very flat. All of the tables had glass on them. I would always get iced tea, and there was quite a bit of condensation on the glass. As the tea warmed to room temperature, the glass would start moving across the table. I always thought it was just funny to see it happen, and my 4 year old thinks it's just magic. :)

I'd never thought about that phenomenon with respect to the moving rocks, but it makes perfect sense!

Re:One possibilty

[Spikeles]

I've seen this happen with cold Coke cans straight from the fridge, not sure if it's caused by the same effect though.

Re:Global Warming

[Broken scope]

Man I just couldn't pick between.

1:But the Teutonic order wasn't formed till the end of the 12th century!

2: Man i really am glad science moved away from that medieval idea of plate tectonics.

Re:Global Warming

[arktemplar]

Now teutonics is accepted by most

tectonics is accepted by most.

Re:Global Warming

[Broken scope]

God damnit, you just missed an opportunity for comedy gold.

Hmm

[scubamage]

This is really cool actually. My guess would be high wind, tied with a low friction surface. Long flat stretches of land tend to equate to massively strong winds. The ground is bone dry, so I'd guess that adding water is going to first add a layer of water that the rock would travel on, and not so much the ground itself. As the water begins to soak into the ground the rock will face more and more resistance because its traveling on progressively more silt and clay than water. Has anyone seen any arial photos of these guys? If something like this was the case the trail they carve into the ground would start off extremely shallow and get progressively deeper as it travels. Also, maybe brine shrimp have something to do with it? Crazy I know, but under a rock would be a cool place to keep eggs, and the addition of water tends to bring flats alive.

We must consider

[Technopaladin]

Really it's not WHY the rocks move...but how do we stop them?

So simple!

[Anonymous Coward]

Pfft this is no mystery. It's pretty obvious that it is Chuck Norris moving the rocks.

Re:Quick! Alert the creationists!

[Anonymous Coward]

My 'a flaming troll atheist' what?

POTC3

[Aubrius]

Perhaps Jack Sparrow has been licking the rocks again.

No, you've got it all wrong.

[Radon360]

No, no, no. You've misread the summary. They're talking about granite, not grants.

Okay, I'll promise be "gneiss" in my responses to future posts, and maybe I "shale" dispense with the bad puns.

(ducks)

answer:

[teknopurge]

Chairs.

Developers... Developers ..Developers.... Developers.. Developers.... Developers.. Developers ...Developers Developers...

Re:Global Warming

[arktemplar]

eg. ?

Gothics was accpeted earlier but now it is teutonics that is accepted by most ?

Age of Empires II had teutons as a civ. I am guessing some jokes can be made using that as well, a teutonic knight flood caused the masses to start accepting the concept of teutonics ?

Everything must be ruled in or out, but...

[ackthpt]

Re:Any word on magnetic influence? I'd guess it isn't wind...are these rocks ferrous? Or...maybe the earth is tilting on its side...weird stuff like that always happens here...I think our perspective of it is just off a bit.

I've camped a few times at Texas Spring campground in Death Valley. Nice place in the right times of the year. One year, however, the wind blew all night at about 40 knots. Nearly took me and my tent away. There are sand dunes to the north of the valley, too. I expect the winds there are more than up to the task of pushing around rocks on moist clay. Perhaps most enigmatic is the question, 'Why don't these larger rocks sink into the mud?' Though with strong enough winds, I imagine they could get a move on again.

Crop circles.

[iknownuttin]

Crop circles happened in a similar way.

Re:Quick! Alert the creationists!

[Anonymous Coward]

Finally! Concrete proof of creationism!

Rock solid too!

It is simple...

[radiumhahn]

The lake bed has a very gradual slope towards the areas where the lake is deepest when water is present. When the lake is dry the force of friction is too high for the rocks to move. When the lake is slippery with mud and water the wind helps the rocks fall towards the bottom of the bowl. Its a lake bed... it is bowl shaped. The combination of gravity, wind, flowing water, and reduce coefficients of friction allow the rocks to slowly fall.

Re:It is simple...

[Fantastic Lad]

The lake bed is famous for being almost perfectly flat, which makes sense; wet mud contained in a many-miles across caldera would tend to even itself out over time. In any case, the slide direction of the rocks matches wind direction, as was shown with one 7-year study with tagged stones.

-FL

That was Strangely Topical.

[Smordnys s'regrepsA]

Rick Rolled while Reading about Rolling Rock Research, by a link Represented as Relevant.

I Require you Rectify this Rankling Repugnance.


Regards,
Ryan

Re:That was Strangely Topical.

[Anonymous Coward]

Anonymous alliteration allows Alachua activist an apple.

My God! There's nothing like a good wordpay!

Favorite trek quote

[the_fat_kid]

Damn it Jim, I'm a doctor not a brick layer

Ragnarok

[ravensee]

They're coming in the name of rock and roll. Nothing gonna stop them now.

Boulder Motion Energy Vectors

[Anonymous Coward]

I'd look at the shape of the surface of the lakebed especially when wet.

Gravity induces a lot of energy into massive objects which incidentally required a lot of energy to move.
If the surface forms a concave up structure I would expect the boulders to move toward the lowest points in the lakebed.
The wind may help induce the motion by "rocking" the boulders on the surface while it is wet.

It may be more like a slow motion boulder falling toward the lakebed's depths, slowed by friction.

Daft Clown

Problem with the ice or even water theory

[SmallFurryCreature]

The cracked effect is what you get when muds dries out, the effect is NOT visible in the trails. How can this be IF the rocks moved when the mud was still there? There is a cracked effect in the trail but it is crushed, the effect you would expect if the rocks had been moved AFTER the ripple effect had already started to form, AFTER the mud started to dry or even when it was already dry.

But if the rocks moved on ice then AFTER the ice melted there would be mud, that if dried would show the same pattern all around the newly positioned rock with just the ridges of the trail left. NOT flattened dried mud.

As for purely the wind moving them, how fast do the winds get there anyway? Wind can be extremely powerfull even in areas with lots of obstructions, in open areas, well if it can pick up/move trucks, why not rocks? Far heavier things are lifted up by air alone, how do you think aircraft work?

Re:Problem with the ice or even water theory

[Reziac]

Winds there can easily hit 80mph. I'm about 100 miles away and I've seen 84mph here, and I've got way less canyon handy to generate high-powered wind with. It wouldn't surprise me if when we have a big blow here, the wind is a good deal harder there.

Last time we had a really big blow, it took out 7 or 8 high-tension towers (the really BIG ones) right behind my place. And I saw a metal 55 gallon drum BOUNDING across my back 40 ... it leapt over my 6 foot high fence and kept right on going.

Re:Problem with the ice or even water theory

[Ecologist in MoValle]

2-shay! As proven by the mashed cracks in the tracks, and the remnants of some surface polygons in the lateral ridges, the rocks obviously moved across a dried and fractured surface. NOT a slimy wet one. Unless one posits a very light precipitation event to dampen and slick-up the surface, but not penetrate to any significant depth. Lack of a "terminal moraine" is also odd, but completely disproves any theory which posits that the rocks moved over a muddy surface. As any kid will tell you: you can't push anything through mud without it piling up (very quickly) in front.

Re:Problem with the ice or even water theory

[thatwouldbeme]

The cracked and dried pattern may not be formed in a single step but rather may be the accumulated effect of many wetting and drying cycles over time. One would then expect the pattern not to be found in the same degree on the trails since the smearing disrupts the chunking of the mud by breaking it down into finer parts, much like the way a freshly tilled garden patch will not immediately return to the caked, cracked look it had before after merely a single rainfall.

Hermit Snails

[infonography]

Just like in the sea animals who need protection will find vacant shells to hide in. Since shells are rare above the water, these snails use empty rocks.

Much like Mexican Jumping beans, they die out when they can't find food.

Sad really.

Re:Global Warming

[Cassius Corodes]

Last I heard the teutonic plate theory drowned under the thin ice while it was battling for superiority with the Russian cossack theory

Did you watch that video or RTFA?

[mcvos]

While the video is interesting, it does not show moving rocks. It merely presents one of the theories (the disproven one, according to TFA) as fact.

Also, the video doesn't say the rocks are pushed by water, but dragged by ice which is pushed by the wind. Water, ice and wind are all mentioned in the article.

So while your video is cool, your presentation of it sucks.

Google Map gave me the answer ...

[geantvert]

... the rocks are trying to leave California!

Re:Global Warming

[Anonymous Coward]

Hahhah that has to be one of the funniest comments I've read on slashdot. I love it.

This is so obvious...

[Anonymous Coward]

What's wrong with you people? These are obviously giant stone-shelled snails.

Leave these rocks alone

[pugugly]

Don't be a playa hater!

(Nobody made that pun yet? I'm so shocked)

Pug

occam's razor?

[Some_Llama]

like crop circles couldn't this just be people moving them? there wouldn't be any footprints since the dried mud is so hard?

Re:occam's razor?

[ribman]

I think the little "waves" on either side are pushed up mounds of dried mud. ie: the rocks moved when the mud was wet, therefore personal levitation would be required to not leave footprints, unless the persons were stone-wraiths and can form the dried earth with their hands as if it is wet. :)

Re:occam's razor?

[Some_Llama]

"I think the little "waves" on either side are pushed up mounds of dried mud. ie: the rocks moved when the mud was wet, therefore personal levitation would be required to not leave footprints, unless the persons were stone-wraiths and can form the dried earth with their hands as if it is wet. :)"

sarcasm aside, it could also be pushed up dry mud that was melted into mounds by rain later on...if you looks at the tracks, the clumps of dried mud in the tracks still have the lines and grooves defining each clump as the surrounding non distribued mud.. if it was slid when it was wet then it would not look the same and would be dried and clear like the surrounding mud.

Not rocks!

[MikeDirnt69]

I bet those turtles are mocking of us!

Amazing how your video shows no moving rocks...

[Roger Wilcox]

60 seconds of watching your 5 second google result reveals that you are putting us on.

There was no footage of moving rocks, just speculation like every other examination of the issue.

Wikipedia Entry

[khoren]

There is a very good article regarding this at wikipedia: http://en.wikipedia.org/wiki/Sailing_stones

my name is Occam

[Anonymous Coward]

Seriously people, why are you looking past the obvious. People are moving the rocks. The only unknown part of this mystery is why and how.

Good God

[BigBadBus]

I first heard about this story about 1982 - and it was old news then! Slow day for news, Slashdot?

Re:Global Warming

[Anonymous Coward]

don't be so sarcastic. He clearly meant Technotronic Plate Movement. Sheesh.

wind moves ice sheets, which push the rocks

[Anonymous Coward]

I remember watching a video that explains this phenomenon -
Ice builds up during winter and surrounds the rocks. When the ice starts to melt, it breaks apart... Wind blows the ice sheets, and the force allows the ice to move the rocks along the mud, creating the illusion that the rocks moved by themselves.

Re:Global Warming

[Grishnakh]

That's no typo, it's an indication of idiocy. If it was a typo, 1) it would be easy to see how the error would be made, as the switched letters would normally be close together on the keyboard. 'c' and 'u' are reached with different hands on a QWERTY keyboard. They're close together on a Dvorak keyboard, however, but it's highly unlikely this poster uses Dvorak. 2) the mistake would only have been committed once. This poster repeated the exact same mistake, showing that he actually thinks "teutonics" has something to do with geology rather than Germans.

After committing an error like this, it's safe to assume that that poster's opinions can be laughed at and ignored.

Ghosts

[Nom du Keyboard]

Poltergeists.

Name Those Rocks

[Nom du Keyboard]

Rocks this talented need names.

I suggest Keith Richards for the first one.

GPS paths for over 150 sliding rocks

[xPsi]

For those insisting someone track the rocks with GPS, check out this web page with a list of GPS paths for about 162 individual rocks (work done circa 1996). For those still interested, be sure and check out the associated Ph.D. dissertation and detailed California Geology article linked at that site. Still no web cams, but this animation is amusing (but probably staged).

Isn't it obvious....

[Kwirl]

The rocks don't move, Chuck Norris kicks the earth and it moves while the rocks stay in place, as the Chuck has commanded.

Re:Global Warming

[Eternauta3k]

After committing an error like this, it's safe to assume that that poster's opinions can be laughed at and ignored.

*blink*
Ok, I actually hate the "science has to believe every crackpot!!1" crowd, but this is kinda extreme.

Scientific method, anyone?

[Desert Tripper]

Why don't the scientists, instead of being baffled, do what they know best? They could purloin a sample of the lakebed (assuming the NPS would let them borrow enough for a test), borrow one of the moving rocks, put them in a chamber which simulates various rain and wind conditions, and see what happens over a period of time. Barring a supernatural explanation for the movement, they should see something happen. I'd love to camp out there a few months during the wet season (or what passes for a wet season in DV) and watch them, if the pay was right...

Hydroplaning

[Weaselmancer]

Maybe the rocks hydroplane and sort of skip across the muddy surface without building up much of a wave in front of them.

Re:Global Warming

[toadlife]

After committing an error like this, it's safe to assume that that poster's opinions can be laughed at and ignored.

Alternately, we could infer that the poster was simply making a joke and you are a pedant.

Eddy Currents and Sand

[adius]

Could it be a combination of Eddy currents magnified by the sand(quartz?)?? The Earth travels at 1000mph. Has someone ever taken electronic measurements?

Re:Eddy Currents and Sand

[Macgrrl]

I thought Eddy was in the space-time continuium?

Re:Global Warming

[Grishnakh]

No, looking at that poster's entire post, there was no apparent humor in it at all. If it were sarcasm, it would have been a little more obvious than that. I think it's much safer to assume the poster is an idiot.

I for one...

[Karel Jansens]

What? They're rocks! They move! I'm not going to piss them off.

BOFH explanation

[kaoshin]

This incident is clearly the product of dereferenced topology anomolies though localised environmental underflows may have resulted in a marked geological destabilization.

The best slashdot post ever!!

[Anonymous Coward]

I nominate this as funniest post I've ever read on slashdot, I'm still laughing as I type.

Olny an absolute moron!!!

[Anonymous Coward]

If the photos are untouched, only an absolute *moron* would suggest that these stones were moved by wind. They most certainly floated via an effect not so known as "spooky-surface tention". This effect is rare but well documented [reference needed] and originates in nether the regions of Lapland. See the old man with a red, four square, tassled hat. He elevates one hand touching the green bands that reach down from the night sky. With his other hand grasps the earth. Thusly connecting the heavens and the Erath the old man causes a thin but heavy mist of elemental water to percipitat on various dry planes that are found below sea level. On this percipitate even large boulders have been known to float as great ships on the great ocien.

well, duh!

[Anonymous Coward]

The dang sandworms come up underneath them and bump them a little! Where's the big mystery?

    And if it isn't the sandworms, well, it's them giant ants! They ..uhhh...were over the border at the testing range and...uhh..saw some dung beetles! That's the ticket! Saw the dung beetles and decided to try their luck at pushing stuff around! And there's no tracks because the wind blows the tracks away, not blows the rocks around , that's just silly, plus, no proof! If people see UFOs yet other people claim no proof, sp be it! Well, just because some rocks *looked* like they moved, that is no proof! Photoshop! Swamp..uhh..Desert gas! Those aren't rocks, those are *weather balloons*!! Of course the wind can blow around 9/10ths deflated weather balloons!

Eggheads, can't see the forest for the trees sometimes..walk..chew gum...go to school with shorts on the outside of their pants...double duh... wind pushing the heavy rocks..uh huh, s-u-r-r-r-r-r-e they do... ritalin junkies... I bet they can count toothpicks though!

Re:Global Warming

[Anonymous Coward]

Dan,

Why don't you just chill out? You are the one that looks like an idiot.

My theory...

[Anonymous Coward]

I believe the rocks are moved by small tectonic tremors, which vibrates them causing them to shift in one direction or another in accordance to the local slope and properties of the soil on which they rest.

Over the course of weeks, months, years, the rocks carve a path on the ground.

migration?

[pileated]

migration?

(the whole point of my previously succinct comment has been obviated by slashdot's insistence that i actually include a comment)! there really should be no text here.

it was a joke, but one that came about by considering the possibility of some sort of magnetic force and then remembering that bird migration is often explained in part by magnetism.

So, Test the Wind Theory

[reallocate]

If it is the wind, it ought to be easy to test. Just soak some of the desert floor surrounding a rock, generate a breeze of sufficent force, and see what happens.

Not enough information

[Anonymous Coward]

They don't show the start of the trails... obviously these rocks are falling down from the mountains surrounding the lake bed (they're obviously not popping up from under the mud!), and the fall down the slope of the mountain should be enough to start them in motion. Once they start their slide, wind & water movement might be enough to prolong their motion. Not sure what the specific density of these rocks is, but if it is anything close to that of water, they would be quite easy to move when the lake bed is flooded... which is why nobody has seen them move; they are underwater when they do.

Re:Global Warming

[Anonymous Coward]

Science can't explain a few rocks scooting over the desert because they rarely scoot over the desert and nobody cares. The weather is more active than during two of six monitored winters (Wikipedia).

Water currents

[lnxpilot]

I would guess, it's this process:
- the lake-bed fills up with runoff water after rain
- the wind creates waves on the surface
- the rocks slide on the slippery mud, followind the strongest water currents

Water has much more mass (than air), plus immersed rocks become lighter.

Sherlock says: Humans

[PietjeJantje]

Everything indicates the rocks are moved by humans. It's an attempt to create a misery, like Loch Ness or the grain circles. Each article about the rocks states, just as with the grain circles, that there was no evidence of human activity - while you can easily walk around without leaving trails, especially behind the rocks, and if you leave tails there you can clear them. Rather suspicious how easily it is dismissed. What did Sherlock say about elimitating the impossible? The sliding rocks leaves mud at he sides of the trail in many pictures, up to an inch high or so. With the required forces of wind or water, this would have been wiped away. The sliding rocks pushes into the ground in many pictures, evidence of much frictional forces at work. We can eliminate ice and sliding. We have eliminated the elements. What we can't eliminate is some guys pushing the rocks forward deep in the night and wiping any footsteps - if their weight leaves any at all to start of with. We have eliminated the impossible, so what remains is the only possible option: humans moved the rocks.

Re:Global Warming

[Mathinker]

> After committing an error like this, it's safe to assume that that poster's opinions
> can be laughed at and ignored.

I see that your grasp of human neurology is laughable. After committing an err...

Oh, never mind. I'd recommend you read a few advanced neurology texts dealing with the remarkable effects of selective brain damage, but I'm in doubt that your own neurological framework is plastic enough to accept that the logical validity of an argument has little to do with the linguistic capabilities of the positor.

The answer is ice

[Anonymous Coward]

The answer is shown here:

http://www.youtube.com/watch?v=u1hoiHvOeGc

Test with a scaled model

[gorrepati]

Can't they test the theory with mud from death valley, in a small tray and a fan? It seems obvious..

debunked

[hpavc]

this has been show with timed lapsed photography to be a function of extreme cold / heat and wind. there are some lake bed videos on youtube. boing boing had this a few months ago.

Re:debunked

[Devistater]

Linkage?

The most interesting theory I've read

[murderlegendre]

.. suggests that they are migrating

But I can't swallow it.

Re:The most interesting theory I've read

[Dunbal]

suggests that they are migrating

      Or it could be some sort of complicated mating dance between rocks, before they rub together and eventually produce mountains in geological time... :)

Conan Doyle was a fiction author.

[Fantastic Lad]

We have eliminated the elements.

You'll have to speak for yourself on that count.

Each article about the rocks states, just as with the grain circles, that there was no evidence of human activity - while you can easily walk around without leaving trails, especially behind the rocks, and if you leave tails there you can clear them.

Easily? You really need to explain that process before you can say such a thing. --Have you ever walked on a mud flat before? I have. 'Easy' is the last adjective I'd use. 'Virtually impossible' is closer to the truth. And keep in mind, we're talking about removing foot prints to and from the sites of hundreds of stones, not just along the path of each stone. Not to mention that many of the rocks are mere pebbles, which leave trails too thin to walk along. We're also talking about a phenomenon which has been around for a very long time. Have pranksters been passing down the hoax from father to son for generations? I think the wind model perhaps mixed with some other force, like water currents or tidal forces or something makes far more sense than pranksters.

One scientist, Dr. Robert P. Sharp, supports this theory. Sharp, a professor of geology at the California Institute of Technology embarked on a seven-year study of this curious wonder. He tagged the positions of thirty stones and watched them for about one year. He recorded the weather conditions after each move. To no one's surprise, all but two of them moved in the directions of the prevailing winds. A nine-ounce stone moved 690 feet in one giant slide. Another stone moved 860 feet in a series of moves.

Crop Circles are even more fascinating by far. . . Many formations exhibit exploded burn marks on the jointed part of the stalk where the bend takes place. In a small number of circles, the seeds have actually been rendered magnetic, (the cause of which, it was determined, was due to iron in the soil somehow bonding and forming into microscopic spheres which lifted and became encrusted into the crevices of all the seeds within the formation). Also the specific weave patterns with which the stalks are folded down in non-hoax circles belies a level of complexity which cannot be achieved by a couple of human pranksters with planks and ropes. As well, the no-footprints issue remains, especially on earth which is dry and crumbly, where footprints would be easily noted. A documentary, available at your local video store, called "Crop Circles, the Search for Truth" is really informative. It also captures on film some of the unmarked black helicopters which have been reported on numerous occasions buzzing formations, as well as an account of how one lead researcher was threatened by the CIA to publicly retract his work. Fascinating stuff.

Sherlock Holmes, as cool as he was, remains a fictional character. Crop circles and sliding stones exist in the real world.

-FL

Re:Conan Doyle was a fiction author.

[PietjeJantje]

Wow, you did so well until the crop circle bit. There's something full of joy, sad, and disturbing at the same time about denying fine people like Doug Bower and Dave Chorley their hoax, and I applaud you for it, sir.

Re:Conan Doyle was a fiction author.

[Fantastic Lad]

Wow, you did so well until the crop circle bit. There's something full of joy, sad, and disturbing at the same time about denying fine people like Doug Bower and Dave Chorley their hoax, and I applaud you for it, sir.

Heck, applaud Doug and Dave. After all, according to the swamp-gas view point, those jokers were responsible for a couple thousand circles, numerous of which appeared on the other side of the planet. Also. . . Magnetic seeds, dude. Radiation burns. Black helicopters. --And I failed to mention genetic anomolies in sample versus control seeds. It's all in the evidence room for anybody who cares to look.

Doug and Dave were just a couple of jokers designed to create confusion. And hey, it worked. --Everybody is ignoring the undeniable proof positive evidence of actual alien contact with our world going on right now. Everybody loves SETI, but they ignore crop circles? Sheesh. You'd think with all the people who are fans of Star Trek and the Matrix and general sci-fi. . . It's as if we're living in one of those episodes where all the people have been hypnotized and only the plucky main character has enough intelligence to see through the illusion and enough guts to do something about it. Everybody who enjoys fiction of that kind thinks that they'd be brave and smart enough to accomplish such feats were they the ones in the story, but the reality is that most people are red shirts.

Now that's sad and disturbing. But not really all that joyful. . .

-FL

Re:Conan Doyle was a fiction author.

[PietjeJantje]

Any defining theories about UFO's and Loch Ness to close? PS: time to visit the shrink, buddy.

Re:Conan Doyle was a fiction author.

[Fantastic Lad]

Any defining theories about UFO's and Loch Ness to close? PS: time to visit the shrink, buddy.

You're not so big on the whole thinking and exploring thing, are you? I don't believe any of my posts to you have been out of order or without plenty of uncontested examples which are freely verifiable to anybody who has even the slightest spark of curiosity. So what's the problem?

Hint: If you strive to live within a belief system which is pre-defined with needlessly tight parameters, then you're going to end up assuming ridiculous things, like pranksters pushing hundreds of rocks around the Death Valley mud flats and then tip-toeing back out in the dead of night.

If you were wrong about that, (and you were), then just think of all the other things you are utterly clueless about.

-FL

it's about time...

[binarybum]

I've been doing this for years, and finally it got some attention. Now I can focus my efforts on shaping cow-pies such that they vaguely resemble the cast of "friends" - it's going to drive people wild.

Discussed in Skeptoid podcast

[jasoneth]

The Living Stones of Death Valley episode (January 2007, link includes transcript) of the Skeptoid podcast describes the various theories, as well as probably the most plausible explanation I've heard so far. An excellent application of scientific skepticism.

Vista is based on these rocks

[scruffy]

When Vista needs to determine whether you have permission to copy any particular bit, the computer implemented by the movement of these rocks is queried.

this is so easy to explain

[Lu]

1). rain, enough to saturate the mud and leave an inch or two of water on top

2). cold, freeze the water

3). more rain, which will work down through miscellaneous small cracks in the ice and float that frozen layer, or

4). wind, to move the plates of ice around, with the embedded and now slightly lifted rocks

Won't always work, the rocks won't always get lifted due to weak ice or not enough water underneath, or there won't be enough wind, or the plate of ice won't be big enough to float the rock. Anything can make the process fail, but sometimes it works.

I didn't really think this up, this was all observed and reported by a scientist onsite who witnessed it happening and was subsequently reported on CBS or ABC radio, I heard it. A few years ago.

So, "No one has ever seen them in motion!" is bullwash.

Another unsolved mystery, solved.

You gonna bust me, and make me supply an exact, quotable scientific source? I can't, life is too short. You don't like the explanation, come up with a better one.

I love Racetrack Playa. Bring your camera, get there late afternoon. But be forewarned it can be obnoxiously, irritatingly windy, and cold.

-Luen

I have a new theory ...

[AnneElk]

Can I just say here Chris for one moment that I have a new theory about the racetrack playa?

Ian M. Banks connection?

[javajosh]

Did anyone else notice that the poster tagged his post with "Feersum" and "Enjinn" - this is a far-future science fiction novel by Ian M. Banks. I wonder why he did that...

I don't get it....

[KillzoneNET]

Why not just get a water truck, find a day when it is windy, find a rock, and apply some water to see if it moves? Then apply the same idea if it is cold enough for the flats to turn water to ice?

Can't see why more tests can be made to actually see if there is a result. If there are any that have been made, it would be nice to read about their results (besides ice and stakes).

Re:no buildup in front - buildup in one photo

[cathector]

check this photo from the article.
it's clearly consistent with the rock pushing a considerable build-up, then changing course about ninety degrees and leaving the build-up behind.

GP is right -- ice sheets explain this

[daniel422]

They don't. They're water. They evaporate. The GP is right. If you look at some of the pictures of this phenomenon you'll notice that nearby rocks will also travel in similar paths -- and even sometimes turn. The only thing that would explain this appropriately is ice sheets. Sheets that lock several rocks together across a wide area. Sheets that could have considerable wind resistance -- in a notably hgh wind area.

Re:GP is right -- ice sheets explain this

[dave420]

Clearly you didn't read the article. There is no evidence for the disturbance of an ice sheet. Slick surface + wind is the only theory so far that isn't contradicted by any evidence present at the scene.

Park a camera there. Sometimes science is easy.

[itsybitsy]

Would somebody please park a couple of web enabled video cameras - with stop motion capture - there already. IT should be easy to "see" what's doing it. Maybe you'll also need to park a park ranger there too. The multiple cameras - pointed at each other - are to ensure that no one is tampering with the cameras or the rocks. Sometimes science is easy.

Re:Global Warming

[Mode_Locrian]

And to think that they might have won if it weren't for their silly hats (seriously, a bird's claw on top of your helmet--wtf?).

35 years ago, Teutonics were not accepted

[einhverfr]

This much is actually relatively reasonable. A lot of countries still had hard feelings about WWII.

Now I am not sure what teutonic plates had to do with mountain formation. Wait I know-- the world was created out of the body of a giant. I suppose one could see Midgard as a sort of plate.....

This is fairly similar to tech-tonic theory, which emphasizes the technological capacity of Odin in the story a bit more.

However, the above theories are more or less akin to intelligent design and not accepted by modern science....

whats wrong with this picture? Spolier alert!

[3seas]

flat dry lake bed. you can see its really flat, except for these rocks that slide over the flat.

If the lake bed is dry and flat then where did these rocks come from? Did they float up out of the flat dry lake bed?

Or did they come from one of the surrounding hills. Like down the hill with momentum onto the lake bed and triggered off by triggered by rain creating something like a mud slide for rocks?

Re:whats wrong with this picture? Spolier alert!

[Reziac]

Actually, the lakebed is a thin residue of clay and dust over the top of a jumble of rocks. (If you dig down a couple feet, you hit rocks.) And rocks do tend to work their way up, much like marbles in sand. And some probably fall from the surrounding hills, which are themselves nothing but large rocks with many fractures. Whenever it freezes, pieces break loose and roll down to the flat areas.

New Plan

[spankey51]

1.) Slide rocks across desert... 2.) ??? 3.) Profit!!!

Correction:

[pizpot]

Lame scientists can't figure out why these rocks...

Video: Moving Rocks of Death Valley's Racetrack Pl

[superswede]

This video claims to explain it, but again, there is not really enough shown to be convinced...

Title: Moving Rocks of Death Valley's Racetrack Playa
Description: "Captured on video for the first time: the mysterious forces that move rocks across the surface of Racetrack Playa in California's Death Valley. As featured on Japanese television. Nobody has ever seen these rocks move, but they leave trails across the dried mud surface often hundreds of yards long. But on this cold winter morning, when the snowmelt covered the playa, we finally saw what nobody before had ever captured on film."
Author(?): Brian Dunning, USA.
Added: March 13, 2006
URL: http://www.youtube.com/watch?v=u1hoiHvOeGc

Another theory

[Herby Sagues]

I have another theory for this.
Perhaps, when the ground is wet, there's a mud layer slightly beneath the surface that becomes fluid. Then, tidal foces make the surface to move up and down creating waves. The waves migh be very low amplitude (a few cm could be enough) and low speed/frequency, but enough to make the rocks slowly slide on the dry (or slightly moist) surface.
Does it sound plausible?

Re:Another theory

[somersault]

I just hope you mean tidal forces and not tidal feces

Re:Global Warming

[Grishnakh]

but I'm in doubt that your own neurological framework is plastic enough to accept that the logical validity of an argument has little to do with the linguistic capabilities of the positor.

I'm sorry, but I fail to see how an argument can carry any weight when the arguer doesn't even understand the basic terminology involved in it. This isn't to say the arguer can't make any valid argument at all, as there may be other subjects he's quite competent in, but this would be like me trying to make an argument about the relative merits of Microsoft programming technologies, and not even knowing the proper name of "DirectX", and calling it "DirectZ" instead or somesuch. It's possible there is a valid argument in there, but it's unlikely as the glaring error simply makes the poster look incompetent in that particular field.

Re:Global Warming

[Grishnakh]

I'm not so sure. If it were a simple spelling error, then sure. Most people make spelling errors, especially if they're typing in a hurry (though Firefox's built-in spell check helps reduce this). But an error like this shows the poster doesn't actually know the terminology involved, and if he isn't a crackpot, it at least makes him look like one.

Maybe...

[neurolux]

Maybe they're being chased by the cactus.

I suppose

[Anonymous Coward]

this can have 3 explanations:
1.Science:rocks slide because they dragged by water,wind,spacetime vortices,or migrating birds.The explanation doesn't show how they do it only there,in random manner,without other evidence.
2.Little grey men:they play football with them.
3.The rocks are alive and hate water.
None are reasonable answers.

Re:I suppose

[LibertarianWackJob]

or migrating birds

It's a simple question of weight ratios! A five ounce bird could not carry a one pound coconut!

Solution for Canadians

[Deliveranc3]

There ya go eh?

Seriously those cracks in the desert, there's something splitting them...

Oh, Oh I know the answer on this one.

[John Sokol]

Differential thermal expansion and contraction.
    In the desert there is a large temperature difference between day and night. Every day the rocks expand and contract with the temperature. The clay soil expands and contracts at a different rate & different amount. This allows the rock to creep an almost imperceivable amount with each thermal cycle. Also temperature gradients in the rocks created by the sun striking only one side of the rock in the morning when the rock is cold creates a caterpillar type of wave of expansions that would also have the rock creep towards the eastern sunrise I would expect.

Re:Global Warming

[Mathinker]

> this would be like me trying to make an argument about the relative merits of Microsoft programming technologies,
> and not even knowing the proper name of "DirectX", and calling it "DirectZ"

And what if you're dealing with a vastly experienced DirectX programmer who's recovering from Wernicke's aphasia? Or mild anomia? Or ...

By the way, don't be misled by the contents of that Wikipedia article into thinking people only suffer the exact symptoms stated in it. Aphasias actually have a very wide range of presentations. As I said, you should go read the advanced neurology texts.

I, myself, mispronounced "finite" for what I would guess was about two years of my youth, because I encountered it in mathematics texts without ever having heard anyone actually pronounce it, and just assumed it was "infinite" without the "in". It took several months of hearing it pronounced by others and being corrected once or twice before I actually checked the dictionary. Your argument in effect is that my mathematical ability was lessened in some way during that period because of that. Kind of stupid, no?

for the lulz!

[Anonymous Coward]

they did it for the lulz!

It is not the rock that moves, but the ground

[maxm]

When it rains the ground becomes muddy. The wind then makes the mud move.
Mud running around the stones is what makes the tracks.

It's the lake being blown by the wind

[Anonymous Coward]

Solved LONG ago.

http://digg.com/videos/educational/Those_huge_rocks_moving_in_the_desert_Mystery_revealed

http://www.youtube.com/watch?v=u1hoiHvOeGc

The wind blows the lake around, then at night it freezes and ice drags the rocks.

Gumby -vs- Rockmen of the Moon

[netglen]

"They're only pretending to be rocks" --Gumby

I would strongly suggest that anyone interested

[porkchop_d_clown]

in this check out the wikipedia entry. It explains what research has actually been done into

1. Whether or not the rocks really move (answer: yes)
2. Whether or not they are being dragged by ice (answer: apparently not)
3. How wind and rain could be strong enough (answer: apparently the wind regularly hits 90 mph during the rainy season on the playa.)

Gargoyle rocks

[Anonymous Coward]

The answer is simple. These rocks are gargoylic rocks that move only when no-one is observing them. This was explained in Dr Who.

The Rocks grow Ice Wings???

[rclandrum]

Here's a theory - the rocks grow ice wings. Cold wind blows across the top of the water, causing the portions of rocks that poke up above the water to be colder than the portion of the rock under the water. Water ripples hit the rock and some of the water freezes causing a halo of ice to form around the rock. The wind continues to blow the water across the formed ice sheet, and because the rock is still colder on top, more water freezes near the top center of the sheet than below. Now we end up with an ice sheet surrounding the rock that is curved on top and flat on the bottom. The water drains away/soaks into the ground, leaving the ice sheet with attached rock in the middle exposed to air. Air flows across the now wing-shaped sheet causing lift, and at some point the amount of lift, wind velocity and slipperiness of the mud combine to allow movement. Or perhaps the rocks grow halos of ice, it rains again, and the ice provides enough boyancy to lift the rock. The real answer, of course, is that Elvis landed his saucer and moved them while disguised as Bigfoot.

Rolling tents and dusty solar cells

[LauraLolly]

I camped at Texas Springs for a few weeks with a college geology class. We had 50 knot winds a few days. After the first day, we learned to collapse our tents when we left them, as otherwise they behaved much like tumbleweeds, and fetched up against the nearest obstacle.

For those who think that it's best just to put solar cells out there, powering a webcam, I recommend trying to put out a solar cell and seeing how long it remains viable when dust-covered. Just as dust storms on Mars cause problems for solar cells, dust in Death Valley may also cause problems. Solar cells may well work, but they may not. It's a very dusty environment, and quite hostile.

And yes, frying an egg on the parking lot has been demonstrated at Furnace Creek. Lovely place to be from November through March. Not so much fun the rest of the year.

Pretty obvious to me... hydroplaning

[foniksonik]

When it's wet... before turning to mud, there will be a fine coating of water, which will have surface tension... and there's probably minerals in the soil that enhance that surface tension.

Ever put a cup on a wet table? It slides around with the smallest breeze. If it gets as windy as described, then the combination of surface tension and wind is probably the cause. AKA hydroplaning... in fact the tracks may only be the gouges left when the rocks stop hydroplaning... they may start their slides meters away from the 'trails'.

ever been through a hurricane?

[kraksmoka]

look, anyone who has, and the worst i've seen was Andrew (165 MPH winds) knows that a few hundred pound object is nothing to a gust of wind moving at triple digit speed. rocks are not exactly the most aerodynamic objects on the planet, and as such would be fairly easy to get pushed around on a dry surface, or even a mucky wet one. . . . .

Google Earth?

[ryanw]

Anyone find this location in Google Earth yet? Maybe it would be easy to track by pulling it over the course of a year?

Re:Google Earth?

[Kip]

Asking Google for Racktrack Playa (mentioned in the story) will net you a Wikipedia entry, which has these fun coordinates at the upper right of the page. Click on that, and you'll get a page of links opening that location in various mapping websites and applications including Google Earth.

Or you could just go to 36.68N, 117.56W

The resolution in Google Earth for that location isn't remotely close to being useful for answering this puzzle.

The rocks don't move

[Iowan41]

I thought that had been proven. The tracks are caused by water or wind reacting to the presence of the rocks, giving the illusion of trails.

Re:Global Warming

[LeadSongDog]

because teutonic plate theory was just too crazy to accept... ... although it replaced the even more silly Gaulish plate theory, quickly discarded by history.

The Hellenic plate theory never mounted a serious challenge, as it was smashed by its supporters.

dumb

[Anonymous Coward]

Rain ralls and creates a shallow lake, only millimeters or centimeters thick. at night it turns to ice and the wind blows the rocks across the lake. stop posting old stories as if they're mysteries

Answer:

[skintigh2]

When the lake has a few inches of water in it and freezes over, the ice locks onto the rock and the slightest wind blowing on those millions of square feet of ice will drag the ice (and rock) around. I believe this has already been tested decades ago, but if not is easily testable.

Next "scientist-baffling"-pseudo-science-urban-legend, please.

Because your toilet is not level

[wsanders]

And gravity did the work. Stuff slides around in my kitchen all the time, none of our countertops are level and all it takes is a lubricating layer of water, or a vessel turned upside-down with water sealing the edges, and things turn into little gravity-powered hovercraft.

It WOULD be an interesting theory - by definition lake beds are absolutely level, because they dry out after getting wet. BUT if wind were pushing the lake around while it was full of water, and continued to push until the lake dried out, seems plausible to be that the lake bed could be non-level.

But then, when it got wet enough to let rocks slide around, it would level itself again.

But then, the tilt in the lake bed could build up over time.

OK. who lives close to this place? Nobody.

Sushi Theory

[dakrin9]

Whenever I go to the sushi restaurant and order Green Tea it always comes out in a very hot kettle. After the kettle is placed on my table, after a few minutes my cold glass of water starts sliding all over the table on it's own.

I wonder if it is an affect similiar to this.

Why not combine the two explanations?

[thatwouldbeme]

Rather than being moved by wind in the absence of standing water or by ice in its presence, why couldn't the rocks have been moved by standing water in the absence of ice, the water itself being driven by wind? The presence of the water would reduce the friction through buoyancy and also provide more pushing force via wind-initiated currents. Such currents would tend to prevail in similar directions within localities but differ between them, would allow situations where small rocks but not large ones move, and would tend to leave the stakes unaffected. Extreme examples of parallelism in the tracks could be the result of either ice rafts or floating debris, such as a log, but be the exception rather than the rule. In such cases, one would also expect to have divergences near the end of the trails as the rocks became free of the debris(or as the ice breaks up).

no current ripples either Re:no buildup in front

[gregconquest]

Here is an aerial/satellite view from google maps (full link further below): http://snipurl.com/racetrackplaya The resolution is perhaps greater than one meter, based on the road to the west and the smallest objects (bushes?) visible nearby. The moving rocks in the photos seem to all be much smaller than this resolution, so they're not going to be visible on google maps, but you can look around the field to get an idea of the hydrologic forces in operation based on the very visible erosion patterns. Another thing, two of the rocks in the photos appear very angular -- presumably on the bottom as well. None of the "condensation-pressure-floating" ideas would seem to work on such heavy objects with such a small, irregular footprints. We need photos of the bottom of the rocks, and occasional photos from fixed positions to measure the movement of the rocks. Also notice that there are no wind/current ripples on the mud. This means the mud dried in the absence of strong winds! And water currents? This too would produce ripples, larger dunes... Greg Conquest http://snipurl.com/racetrackplaya is short for http://maps.google.com/maps?q=Racetrack+Playa&ll=36.697105,-117.557552&spn=0.006572,0.014377&t=h&z=16&om=1

Jesus

[Anonymous Coward]

The bed under the rocks is moving

WebDawg...