NASA Reveals Dust Devil Data from Mars

saskboy writes "NASA reports that Martian dust devils could be much more destructive than previously considered. You may remember this past April when it was revealed that whirlwinds actually helped the current rovers by cleaning accumulated dust from their solar cells which increased their energy collection efficiency. But after studying the mini-storms more, they realize that the dust and sand particles could cause static electricity discharges, also known as lightning. The high speed grains of sand blowing around at about 30 meters/second (70 miles per hour) are nothing to blink at either, since they can damage astronauts or equipment on the Martian surface. The height of a Martian dust devil can reach 10km (6 miles), which means it's more like the size of a terran tornado."

Comments

A quick question

[zegebbers]

From the blurb : "The height of a Martian dust devil can reach 10km (6 miles), which means it's more like the size of a terran tornado."

Does that mean that a tornado is only on earth? Why are these referred to as "Dust Devils" and not tornadoes generally? Cheers

Re:A quick question

[msgregory@earthlink.]

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

Re:A quick question

[i8a4re]

My guess is that tornados form from storm clouds where dust devils form due to convection from heating. While they are both vorticies, their origin is what distinguishes them.

Re:A quick question

[aussie_a]

Does that mean that a tornado is only on earth?

No, although Tornadoes may only be found on Earth (I highly doubt it), tyhe fact it's called a dust devil doesn't mean Tornadoes are only found on Earth. It would have been compared with a Tornado, because it's is comparable to a tornado in size only (and most people would have an idea as to what the size would be).

Re:A quick question

[MyLongNickName]

Sorry. That link doesn't answer the grandparent's question.

Re:A quick question

[msgregory@earthlink.]

It says what a dust devil is and that the idea didn't originate from studying Mars.

Re:A quick question

[MyLongNickName]

Does that mean that a tornado is only on earth? Why are these referred to as "Dust Devils" and not tornadoes generally?

Two questions. Show me where the link answers either of them.

Re:A quick question

[msgregory@earthlink.]

It describes what a dust devil is, the implication of the post being that the idea didn't originate from studying Mars.

Re:A quick question

[MyLongNickName]

Answer: It doesn't. It is part of a growing phenomenon on Slashdot. Post a link to wiki that kind of relates to the thread. Someone is impressed that poster knows how to link... and hey it is WIKI after all... it must be informative: let's mod it up!

In actuality, naked links get used by folks to lazy to summarize the information themselves, but want some mod points. I called yours out as the link doesn't even answer his questions.

Have a nice day.

Re:A quick question

[MyLongNickName]

Also, note that after I posted this, the wiki summary came up with the following added line:

Also, like, dust devils are not tornados, because they aren't. Dust devils are primarilly dust, while tornado are primarilly not.

It definitely wasn't there before. Talk about pathetic.

Re:A quick question

[TykeClone]

I'd guess that it's the amount of (destructive) power that differentiates between the two.

Both tornados and dust devils happen when the air close to the ground is warmer than the air up a bit higher. In tornados, there is a lot more power generated over a larger area (and has the potential to do more damage) than a dust devil would.

Because of the thin martian air, the dust devils have little destructive power so they aren't called tornados.

Re:A quick question

[msgregory@earthlink.]

Oh yeah, I put that there so I could get some mod points. Man, I don't know what I'd do without them. I would probably start bitching at every poster you got modded up because I get these withdrawal symptoms, you know, and I start thinking that my judgement about each individual moderation is absolute and that anyone who gets modded up becomes this big criminal that needs to chastised.

Re:A quick question

[Anonymous Coward]

A tornado is a vortex that by definition has to be in contact with both the ground and a cloud base. The Martian vortex under discussion forms in a cloudless environment, therefor it shouldn't be called a tornado. Furthermore, the mechanism that creates and sustains the Martian devils appears to be identical to the mechanism that powers terrestrial dust devils (tornadoes are formed by a different process entirely). Because the Martian vortices do not form under a cloud base, and are created in a manner similar to terrestrial dust devils, it's clear that the appropriate name for the vortex is dust devil, and not tornado. The fact that the Martian whirlwinds may be as powerful as some Earthly tornadoes is not really a good enough reason to call them tornadoes. Dust devils it is.

Re:A quick question

[rejecting]

I hate you all.

Re:A quick question

[bar-agent]

Well, if Martian dust devils are going to be that bad, I vote we call them "dust demons" instead.

Who's with me?

Re:A quick question

[arbitraryaardvark]

From the wiki:
"Also, like, dust devils are not tornados, because they aren't. Dust devils are primarilly dust, while tornado are primarilly not."

That pretty much nails it eh?
Perhaps homeland security will increase spending or mars research to combat the dust devil menace.
Mars - that's no moon.

Re:A quick question

[Rasta Prefect]

Also, note that after I posted this, the wiki summary came up with the following added line:

Also, like, dust devils are not tornados, because they aren't. Dust devils are primarilly dust, while tornado are primarilly not.

It definitely wasn't there before. Talk about pathetic.

And that, for those who were wondering, is why Slashdot doesn't and probably never will allow editing of posts.

Re:A quick question

[timeOday]

I'd guess that it's the amount of (destructive) power that differentiates between the two.

I'd guess so too. And apparently, 70 mph does qualify, albeit in the very weakest category of tornadoes:

F0 light 40-72 mph
F1 moderate 73-112 mph
F2 significant 113-157 mph
F3 severe 158-206 mph
F4 devastating 207-260 mph
F5 incredible 261-318 mph

Re:A quick question

[Alsee]

You posted an interesting link on dust devils, however the other poster was correct... the link did not answer the questions asked. It does not address the dust devil vs tornado issue.

If you meant to provide a general link on dust devils, great. Without labeling it as such it is very easy for people to think it was intended as an answer to the specific questions that were asked and for people to be dissappointed when they read it and not get an answer.

If you thought it did answer the questions, well I read it and I thought about it and I think you're mistaken.

If you want to whine about the mod system, well ok... but I expect you'll continue to get modded to -1 for it if you do. Most people do not want to waste time reading pointless crap. I'd post this reply at zero if Slashdot allowed the option to do so. This very post is mostly worthless crap in a worthless argument. I personally read at 3 most of the time because I simply do not have the time to read hundreds or even thousands of (mostly crap) posts on each story.

If you want to post "bare links", ok.... but they would be much more valuable to other people if you had at least minimal appropriate descriptive text.

-

Re:A quick question

[Deadstick]

They both form from convection.

When the sun heats the ground, the air next to the ground gets hot, expands, becomes less dense than unheated air, becomes buoyant, and rises. Air from less heated ground areas (cultivated fields, for instance) flows radially in to replace the air rising from hotspots (like rocky areas), and owing to some rather complex mathematical considerations, comes in in a spiral path. The air rising from the hotter spots is called a thermal. Buzzards circle in them to stay aloft and hunt with no muscular effort.

As the air rises, it encounters falling pressure, so it expands adiabatically, which causes its temperature to drop. If the thermal is strong enough, the temperature gets down to the condensation temp and water condenses out of it. This forms a cumulus cloud -- the kind that looks like a cauliflower, flat on the bottom and puffy on top. The condensing water gives up its heat of vaporization, which offsets the adiabatic temperature drop, which makes the air more buoyant and the thermal gets stronger. Sailplane pilots seek these out for basically the same reason buzzards do: to stay aloft without an engine.

A dust devil is merely the visual manifestation of a thermal over dusty ground: the circulating wind kicks up dust.

If the thermal is strong enough, the air rises above the freezing level and the water droplets give up their heat of fusion which is added to the heat of vaporization. This condition defines a thunderstorm. All thunderstorms produce rain and hail, although depending on surface conditions, the hail may melt before reaching the ground.

With each of these stages the intensity of the updraft, the speed of the wind flowing in, and the rate of circulation around it increase. At a certain point, the air entering the updraft sees so big a pressure drop that it starts to condense water before reaching the normal condensation level, and that makes a funnel cloud.

Finally, when the funnel cloud grows downward until it meets the dirt, dust and trailers coming up, it's called a tornado.

rj

Re:A quick question

[Anonymous Coward]

I wish Slashdot allowed choosing to post at zero too. I turn off my karma bonus on most of my posts because I don't think they're important enough to warrant it. For off topic posts like this I post AC, just to make the starting score zero.

Re:A quick question

[Anonymous Coward]

Does that mean that a tornado is only on earth? Why are these referred to as "Dust Devils" and not tornadoes generally?

A "Dust Devil", as its name inplies, is spawned by Satan.
A tornado is spawned by God.

More seriously, a dust devil is a kind of tornado, as is a water spout.
Generally, a dust devil is a very weak tornado, the kind that picks up dust, not houses.

Re:A quick question

[sl3xd]

I can walk into a massive dust devil, spin around like the tazmanian devil in looney tunes, act like it's my spinning that's causing the thing to spin. I'll come out generally unharmed. (Maybe a bit irritated from bits of dust hitting my skin, or maybe a bit of dirt in my eyes and/or nostrils -- but otherwise quite unharmed.)

OTOH, I tend to avoid (and flee from) tornadoes, as there's a high degree of certainty if we were to interesect one another, I wouldn't survive.

At 1/100th earth pressure?

[Anonymous Coward]

The martian atmosphere is much thinner.. so it isnt gonna be as powerful as "terrestrial hurricanes" for sure..

Re:At 1/100th earth pressure?

[Anonymous Coward]

The martian atmosphere is much thinner.. so it isnt gonna be as powerful as "terrestrial hurricanes" for sure..
http://bash.org/?1988
kritical matts: bikes go faster than cars...a bike at 60 mph is a lot faster than a car at 60 mph
matts kritical: um no...
kritical matts: um yes
kritical my sisters sport car at 60 mph goes faster than my dads explorer at 60 mph
kritical a bike at 60 mph will blow by a car at 60 mph

Re:At 1/100th earth pressure?

[Anonymous Coward]

A car hitting someone at 60 mph will do a lot more damage than a bike hitting him at 60 mph. You failed it.

Re:At 1/100th earth pressure?

[FLAGGR]

What if its a toy car?

Re:At 1/100th earth pressure?

[Rei]

More specifically, Mars's atmosphere is about 0.7% of ours (incredibly thin); "tenuous" would be a good term for it. Even though energy of wind is proportional to velocity squared, this means that the winds (assuming that they're equal to atmospheric density) have the energy of a 6 mph breeze on Earth.

The problem isn't the force, but the dust. The dust is a problem on its own; it almost seems designed to create static charges and then penetrate tiny cracks in everything around.

Thanks :)

[HG Slashdot]

But after studying the mini-storms more, they realize that the dust and sand particles could cause static electricity discharges, also known as lightning.
Thanks :) I have always been wondering what "lightning" is.

Re:Thanks :)

[Andy Gardner]

What is this, li-ght-ning you speak of?

Re:Thanks :)

[aussie_a]

Thanks :) I have always been wondering what "lightning" is.

Last I knew, most American's (and this website has an American bias) experience with lightning was in the form of the rain-storm type. Lightning of this variety isn't a result of dust and sand particles causing static electricity discharges. On a planet that (as far as I know) has no rain, the idea of lightning, isn't obvious. Even though I know lightning can occur in sandstorms, I had never put this together with lightning on Mars.

So while you got your funny, it really wasn't an accurate post.

Re:Thanks :)

[Alex P Keaton in da]

We get heat lightning out here in Ohio from time to time, separate from storms.
I have what may be a dumb question (There are no dumb questions... Just dumb people asking questions...) but if this thing has rubber tires, couldn't they just put a roll bar on the next one with a lightning rod, and shoot the electricity right out the bottom? Or is the equipment to sensitive to be around a discharge? Electricity has always been something a bit over my head, so if someone on here knows, please share.
That being said- I am glad that we are continuing to check out Mars- I wonder if there will be as much excitement over a manned Mars landing as there was over the Lunar landing...

Re:Thanks :)

[Ice Station Zebra]

I've seen dust devils in the desert pick up small tents and fly them through the air to the amusement of us who knew how to stake our tents.

Re:Thanks :)

[Toutatis]

I have always been wondering what "lightning" is.

Many people are still wondering what "lightning" is.

Re:Thanks :)

[Alsee]

I'd expect the rovers are particularly delicate and that they'd be seriously fried by even the smallest lightning strike anywhere near by. Every ounce is a precious commodity on a space probe. The odds of getting hit are nearly zero, so the added weight of a lightning-hardened system would be a big negative on a cost/benefit basis.

-

Re:Thanks :)

[Enigma_Man]

Electricity as powerful as lightning doesn't care about rubber tires, it'll just go right around them. If lightning travels miles through the sky, and through your car it's not just going to stop there because there are some rubber tires. The equipment on the rovers is no doubt designed to be hearty (It's survived more than a year on another planet with much harsher conditions than earth). But a lightning strike is fairly difficult to route away from electronics without causing some collateral damage.

-Jesse

I walked into a dust devil here on earth...

[vudufixit]

It was in eastern Washington state - many of them were spinning over hot, dry recently tilled farmland.
My friend and I were on a road trip, and I asked him to pull over.
I ran into this thing, and it was really weird - the air around it was still, but the dust devil itself was really windy inside!
It took only a second or two to walk in and out of it, but it was an interesting experience.

Re:I walked into a dust devil here on earth...

[eno2001]

There is nothing like experiencing natural weather first hand. Back in the late 80s (I was about 19) we got a really fast thunderstorm with torrential rain. For some odd reason, I was compelled to take my t-shirt off and run into the middle of my back yard. I ran up and grabbed a towel to stick in the back entrance to my house and then threw the t-shirt, shoes and socks off and ran into the storm. I had a friend over who watched in shock as I did this. Since it was a really hot day (mid 90s) the rain felt really refreshing and the smell of the negative (or is it positive?) ions caused by the lightning was exhilirating. I know it was stupid to run out in the middle of a thunder storm, but I will never forget the experience. It was very different from being caught in the rain while walking somewhere. This was intentional. And I knew where my towel was... ;P (How come stories like these are never told by women on Slashdot?)

Re:I walked into a dust devil here on earth...

[Einherjer]

because while you're out there getting wet, the girls stay in with the other guys who get them wet too :)

Re:I walked into a dust devil here on earth...

[bcmm]

I've been in a dust devil too, in the hot, dry parts in the south-east of Yemen, though it passed over me; I didn't walk into it on purpose.

It should be pointed out to /.ers who've never seen one that earth ones are nothing like as powerful as the Martian variety, and that all you need to do for safety is to wear sunglasses or something over your eyes and a cloth over your mouth and nose so you don't inhale dust/sand.

Re:I walked into a dust devil here on earth...

[bcmm]

P.S.
I dunno, maybe in some parts of the world you get the occasional uber dust devil or something, so don't walk in if you see big things flying around :)

Re:I walked into a dust devil here on earth...

[jbeaupre]

We used to play in them all the time as kids in southern New Mexico. Most were harmless. But the hill behind our apartment would spawn several strong ones a year that would come down and rip the screen doors off our place. I'd have to find them out in the field and nail them back on the door frame.

Re:I walked into a dust devil here on earth...

[pembo13]

You should come to Dominica, in the Caribbean. We get full hurincaes here, but lightning never touches down, so it's quite normal for people to be out in such weather.

Re:I walked into a dust devil here on earth...

[chawly]

You had your pants on ? ( Lack of stupidity is a characteric I've noticed in many women but few men. Could this explain why you never hear about women deliberately wandering about in heavy rain - dressed, half-dressed, or naked ? ) On a really hot day, you can take a cold shower and you'll find the towel right there, where it should be.

Re:I walked into a dust devil here on earth...

[eno2001]

Doesn't compare to feeling rain hitting you in full torrential mode. I suppose if you have a shower that has a 12'x12' square head, you might be able to pull it off.

Wind energy?

[Anonymous Coward]

I know it's a long shot, but couldn't this energy be harnessed in say a decade and make future vehicule be able to function 24/24?

Re:Wind energy?

[aussie_a]

Probably, but the devil of it transporting something that can survive the trip in space and not be destroyed too quickly by sand and dust.

Another problem is, are winds regular and strong enough for the thing to be able to be powered as reliably as solar powered vehicles? If it gets stuck somewhere that isn't windy for a week, that's a week of it being down (once it's reserves run out). On the other hand, the sun rises every day.

Re:Wind energy?

[Anonymous Coward]

I wasn't discounting the use of solar energy. In fact I am envisioning dual power sources.

Not as powerful as tornadoes...

[MadMorf]

The height of a Martian dust devil can reach 10km (6 miles), which means it's more like the size of a terran tornado

But no where near the destructive force of a tornado, which may be why they're calling them dust devils...

It's less than 1/3 the windspeed and since the atmosphere is less dense the total energy will not be anywhere close...

Re:Not as powerful as tornadoes...

[MadMorf]

One more note:

We may not be able to reliably measure their destructive force because there are no trailer parks for them to tear up...

Re:Not as powerful as tornadoes...

[AndroidCat]

We could call them ajax, 'cause it cleans like a white tornado!

Re:Not as powerful as tornadoes...

[Anonymous Coward]

In my part of the country, they are called whirlwinds.

Re:Not as powerful as tornadoes...

[twiddlingbits]

However, the sand particles in the "dust devil" can be quite a problem. They are abrasive and carry static electricity. Could be a problem that say solar cells would get etched by the storms and drop their efficiency. I bet it would play hell with electronics as well, and also with transmission of signals via radio. Not the destructive knock everything in it's path down power of a tornado but nothing to ignore either. The only similar thing on earth would be the large sandstorms they get in the Persian Gulf areas.

Re:Not as powerful as tornadoes...

[EvanED]

It's not just a matter of not measuring them because of a lack of trailer parks, it is reasonable to conclude from this research originally from The Annals of Improbable Research that the lack of trailer parks actually reduces the occurances of tornadoes.

Many of the other variables mentioned as possible influences on the frequency of tornadoes, such as camcorder sales, are also substantially lower or in fact zero on Mars.

Re:Not as powerful as tornadoes...

[igny]

We may not be able to reliably measure their destructive force because there are no trailer parks for them to tear up...

But NASA's Department of Martian Live Video can always borrow some trailers from Miramax or Universal.

Re:Not as powerful as tornadoes...

[caino59]

Ah - but maybe these Dust Devils are why there are none...

Re:Not as powerful as tornadoes...

[chris_mahan]

Could it just possibly be that the absolute absence of trailer parks reduces the chance of tornadoes to zero, making these dust-devils instead?

Ah, I'll go finish my coffee before attempting more humor...

Well then

[MrShaggy]

I guess there is no Tasmanian Devil inside these ?? Or a 'really really big one'. Shagz

Dust Devil on Mars?

[Zweideutig]

How did Royal Appliance Mfg. Co. manage to build a remote control vacuum cleaner within a vacuum? I am confused! Hopefully this isn't just a trade secret, I hope ot find my answer on uspto.com! ;-)

Lightning

[Anonymous Coward]

You can see lightning. Why do we have to speculate about the possibility of lightning on Mars? Given the amount of time we've been staring at Mars with high power telescopes we would surely have seen it if it were there.

Re:Lightning

[AndroidCat]

I don't suppose the rovers have microphones (adjusted for the low pressure)? Most of the time it wouldn't be worth the bandwidth to send back, but the bang and rumble from just one lightning strike would be something. And can you imagine the number of New Age "windstorm on Mars" environmental CDs that NASA could sell?

Re:Lightning

[ToshiroOC]

No, they have no microphones. Mars Polar Lander, the one the crashed, had one but, uh... as would be apparent by its crashed state, we never got data back. I don't know if Phoenix is going to have a microphone or not, but if not, I doubt we'll have audio coming back from Mars any time soon.

Re:Lightning

[AndroidCat]

That's a shame. There might not be much science value in it, but the Sound of Mars would do a lot to make the surface of Mars a real place to the public. (And if we detect Julie Andrews singing "The hiiills are aaalive...", we can mount frikking lasers on the next rovers.)

Grounding to help with static electricity?

[Cyclotron_Boy]

They bring up an interesting problem in the article about the difficulty of cleaning surfaces after a storm- the triboelectric charges wouldn't necessarily have anywhere to bleed off to. Since Earth's ground is relatively wet, simply sticking a copper rod into the ground provides a good path for stray charges to go. Unfortunately, in a dry soil like that of Mars, grounding rods may not provide the level of protection they might on Earth. On the other hand, the reduced atmospheric pressure and lowered breakdown potential might actually help simpler methods like the charge dissipators (so called "static wicks") on plane wings. Basically, as long as there is a sharp point to help field emission and concentrate the E field in a small volume of space, the excess charge is dissipated into the atmosphere.

Re:Grounding to help with static electricity?

[denormaleyes]

The plane is usually constructed with a skin of aluminum that conducts quite nicely, so the lightning heads on out the other side of the plane. The static wicks are more for avoiding problems with radio communications and navigation equipment.

"Sand"

[luna69]

The OP notes the "he high speed grains of sand blowing around at about 30 meters/second".

Just to be clear, we're not talking about "sand" in the sense that your average beachgoer thinks of it. The typical size of the dust grains on Mars is a few tens of microns (say 10-30m or so), which is quite a bit smaller than sand, which ranges from a few hundredths of a millimeter to a couple millimeters in size (roughly, using geological definitions).

Re:"Sand"

[justforaday]

Very true. What they are calling "sand" is actually more on the order of silt or clay in sedimentary geologic terms. There's a picture of a handy little pocket grain size chart here for reference.

Re:"Sand"

[Anonymous Coward]

WTF are you talking!?

The typical size of the dust grains on Mars is a few tens of microns

ten microns = 10um

than sand, which ranges from a few hundredths of a millimeter

hundreths of a millimeter = 10um

So you are saying that they have the same size, aren't you?

(Gratulations to the mods who modded this up. You failed it.)

Re:"Sand"

[Anonymous Coward]

> to a couple millimeters in size

You are an idiot.

Re:"Sand"

[Anonymous Coward]

The idiot is you. Apparently mars sand is just that - fine sand. It's on the lower scale of what is considered terrestial sand, but not smaller.

Re:"Sand"

[luna69]

Wrong.

Wind-blown Martian dust -- which IS different from sand, as is obvious from Mars' low air density/atmospheric pressure -- can be as small as 1 micron. No terrestrial sand is that small, and the VAST majority of terrestrial sand is on the order of a millimeter, much larger than martian dust, even at the high end of its size range.

Please refrain from pointing fingers when you don't know what you're talking about.

Re:"Sand"

[Anonymous Coward]

Quote yourself: "The typical size of the dust grains on Mars is a few tens of microns".

Your original post was stupid and gave a wrong impression: you were talking about tens of microns and hundredths of a milimeter, which is the same but gives to the casual reader the impression that the one is bigger than the other. Learn to express yourself clearly. Or do you want to go into politics?

Re:"Sand"

[luna69]

My original post pointed out that sand, as we think of it, is up "to a couple millimeters in size" and that what's on Mars isn't. No further clarification is necessary, for anyone capable of understanding English. If you were really concerned that there was a slight overlap in the units I used, go fuck yourself.

Quick!

[Mike Savior]

Somebody call the UAC!

Re:Quick!

[Anonymous Coward]

Good sig, but you're missing they're and their.

Re:Quick!

[Mike Savior]

I left "they're" out due to space constraints, and simply because I seem to find "their" used as every phonetic form of the word. I didn't forget!

Re:Quick!

[Anonymous Coward]

And you're missing 'there'.

a terran tornado ?

[MDMurphy]

I was curious to see if the linked article referred to "terran tornados". Nope.

There's a reference to "terrestrial dustdevils", that's close.

I would have been surprised to see sci-fi jargon in the middle of a NASA report.

Uh, oh Toto, I don't think were in Kansas anymore

[nihilistcanada]

Apparently Dorthy got her ass to Mars.

Could Dust Devils be...

[budn3kkid]

a potential cause for the loss of ESA's Beagle2? Maybe it's blown off course during landing, or maybe a chance that a Dust Devil went past the lander right after landing and blew it apart? Then maybe it was torn apart and buried under the sand? It would explain why the lander still couldn't be found, 'cause maybe it's not in one piece anymore. Considering this discovery, maybe it would be prudent to figure in a method to avoid lander losses should it encounter any Dust Devils DURING the landig process, in addition to protecting against it AFTER landing. Some sort of new material would have to be developed if it were to withstand constant sand-blasting all year round, considered if Humans are to be sent to Mars for colonisation.

Re:Could Dust Devils be...

[hilaryduff]

maybe, or it couldve been a rushed, under-funded and over-hyped mission that had a slim chance of actual success. its still less embarrassing than mixing up footpounds and newtons like that NASA probe

Re:Could Dust Devils be...

[sznupi]

You're hallucinating...

ok, I'll expalin. Mars atmosphere != Earth atmosphere. In the same sense as 200kmph tornado is much less devastating than hypothetical 200kmph wall of water. Got it?
(and the Beagle probably has been found)

Re:Could Dust Devils be...

[pedroloco]

(and the Beagle probably has been found)

Nope, at least not convincingly. The Mars Orbiter Camera (MOC) found a dark spot near the predicted Beagle landing site, but further imaging showed that spot to be a small impact crater with wind-blown sediment on its floor, which is not consistent with an impact as recent as late 2003.

From the MSSS link: Based on the MGS MOC imaging campaign and subsequent analyses, no incontrovertible evidence of the Beagle 2 lander was found within the areas imaged by MOC.

Re:Could Dust Devils be...

[dave1g]

Ms. Duff a foot pound is a unit of torque I would assume, and newton is force, I think you meant they mixed up pounds and newtons.

Re:Could Dust Devils be...

[hilaryduff]

harvard didnt send me the email about such things yet. will it be on the test?

Re:Could Dust Devils be...

[dave1g]

LOL I didnt know about this.

http://www.google.com/search?hl=en&q=hilaryduff+ha rvard&btnG=Google+Search

Re:Uh, oh Toto, I don't think were in Kansas anymo

[Anonymous Coward]

I've heard that she likes that sort of thing.

Thank you Dr. Obvious

[Gothmolly]

"static electricity discharges, also known as lightning"
REALLY? Lightning is electricity? Amazing! All along we thought it was from the Gods being angry! Maybe someone should take a kite, and put a key on the string, and fly it in a thunderstorm...

This should have been in the poll

[idonthack]

This should have been in the natural disasters poll :)

Typical Windspeeds on Mars

[jong99]

Windspeeds of 70mph are not really excessive on Mars.

The Mariner probes detected a typical wind speed of 125mph and gusts of 300-375mph. (source)

The reason that these winds are never mentioned is that the atmosphere is so thin (0.75% of the density of Earth's) so they don't have that much force behind them.

like a common F0-F1 tornado here on earth

[weathergeek]

70mph is almost enough to push a mobile home off its foundation. I imagine it'll push a rover out of the way, or a dough-boy-looking human.

Re:like a common F0-F1 tornado here on earth

[aXis100]

Not on Mars it wouldnt. Because the atmosphere is so thin, the wind pressure at 70mph is much, much lower.

Re:like a common F0-F1 tornado here on earth

[sznupi]

Ypu're forgetting about the fact that there isn't enough pressure on Mars to do something like this...

Re:like a common F0-F1 tornado here on earth

[weathergeek]

Yep, good point guys. Forgot about the density difference :)

Now we can find life on Mars, at last

[AtariAmarok]

At last, we have a fairly reliable way to zero in and find life on Mars. Just find where these funnel-clouds congregate, and you are sure to find Martian trailer parks. Granted, I'm not sure that discovering "green trash" is the type of close encounter everyone's been expecting, but it is better than nothing.

Re:Now we can find life on Mars, at last

[Anonymous Coward]

Would they have green lawn flamingos?

Damage astronauts?

[Anonymous Coward]

since they can damage astronauts or equipment on the Martian surface.

As far as I know, there are no astronauts on Mars so it is not possible for them to be damaged. However, they could be damaged if they were there. Is some kind of backwards Capricorn 1? We actually go there, but don't tell anyone? Conspiracy theorists awake!

For those too lazy to read TFA, as it turns out...

[Kirkoff]

The Devil is in the Details.

Confusion

[Ark42]

The page you link to, titled "How is a plane protected from Lightning strikes?" references a page "Wingtips by The 737 Technical Site", which says about the static wicks: Note that they are not for lightning protection.

So, I am a little confused here. They obviously stop some smaller charge build-ups, but what about the lightning issue? Yes or no, and if no, what does protect an airplain from lightning, other then not flying into a storm?

Tall astronauts not an option

[E IS mC(Square)]

>>The height of a Martian dust devil can reach 10km (6 miles)

So, that leaves out even the last option of sending tall astronauts to Mars. :-(

static discharge

[Anonymous Coward]

Damn Marsian and their static discharges...

Damage astronauts?

[going_the_2Rpi_way]

The high speed grains of sand blowing around at about 30 meters/second (70 miles per hour) are nothing to blink at either, since they can damage astronauts or equipment on the Martian surface.

Damage astronauts eh? That doesn't sound good. If it wears and tears on the EVA suits that's bad but if it damages the astronauts that's real bad. I think the state of an astronaut on Mars subject to such elemental damage probably changes in quanta (alive vs. not alive).

New term: "Dustinado"

[Tablizer]

nuf sed

Terra

[DragonHawk]

I saw and checked the same thing.

It really irrirates me when SF people (who often should know better). Terra is nothing more then the Latin word for "earth" or "land". It has no more implict value or distiction or anything else over modern-English "Earth". Since all space-traveling cultures speak English anyway (just watch any TV show or movie), "Earth" would be a lot more appropriate then "Terra" ever would.

As you note, the correct term for "occuring on Earth" is "terrestrial" (which does derive from the same root word, but that ain't the same thing).

Problem Solved

[adius]

>"since they can damage astronauts or equipment on the Martian surface".

Just make sure the astronauts don't take off their space suits.

blink

[tverbeek]

The high speed grains of sand blowing around at about 30 meters/second (70 miles per hour) are nothing to blink at either,

I dunno... they sound like a good reason to blink, if you ask me.

Re:blink

[WilliamSChips]

It would be better to completely close your eyes

Better whirlwind videos

[FleaPlus]

A couple of months ago NASA posted some even better videos of the Martian dust devils, available here:

http://photojournal.jpl.nasa.gov/catalog/PIA07139
http://photojournal.jpl.nasa.gov/catalog/PIA07140
http://photojournal.jpl.nasa.gov/catalog/PIA07138

There's also a rather neat video of Opportunity escaping from the sand trap.

If your house has wheels...

[idonthack]

...then YOUUUU might be a green-neck!
---
I started with nothing and I still have most of it left.
Generated by SlashdotRndSig via GreaseMonkey

Where are the Redneck trailers?

[Anonymous Coward]

I realy expected to see them getting swept away by that thing