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You can also always see the (unofficial) briefing transcripts at Adot's Notblog almost immediately. He does a pretty good job transcribing them as they happen.

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For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

Isn't the atmosphere of Mars only a few percent as dense as Earth's atmosphere?

Doesn't seem like the swooshing of the diffuse Martian atmosphere would provide enough force to shove even a highly-engineered tumbleweed around...

The atmosphere of Mars is 96 percent carbon dioxide, about 3 percent nitrogen and 1 percent other stuff, including water vapor and a little bit of oxygen. And it is a very thin atmosphere. The average air pressure there is only about 1 percent of Earth's.

However, it has enough of an atmosphere to have wind. As a matter of fact, because the atmosphere is so thin, the wind reaches very high speeds.
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In the 1970s, NASA's Viking landers found the top wind speed on Mars was about 60 mph and the average was around 20 mph.

That's enough wind to kick up huge dust storms that can go on for weeks and cover the entire planet.

can't they do any better with the incredible lag due to the distance between Earth and Mars?

Atmosphere

The atmosphere of Mars is quite different from that of Earth. It is composed primarily of carbon dioxide with small amounts of other gases. The six most common components of the atmosphere are:

• Carbon Dioxide (CO2): 95.32%
• Nitrogen (N2): 2.7%
• Argon (Ar): 1.6%
• Oxygen (O2): 0.13%
• Water (H2O): 0.03%
• Neon (Ne): 0.00025 %

Martian air contains only about 1/1,000 as much water as our air, but even this small amount can condense out, forming clouds that ride high in the atmosphere or swirl around the slopes of towering volcanoes. Local patches of early morning fog can form in valleys. At the Viking Lander 2 site, a thin layer of water frost covered the ground each winter.

There is evidence that in the past a denser martian atmosphere may have allowed water to flow on the planet. Physical features closely resembling shorelines, gorges, riverbeds and islands suggest that great rivers once marked the planet.

Temperature and Pressure

The average recorded temperature on Mars is -63 C (-81 F) with a maximum temperature of 20 C (68 F) and a minimum of -140 C (-220 F).

Barometric pressure varies at each landing site on a semiannual basis. Carbon dioxide, the major constituent of the atmosphere, freezes out to form an immense polar cap, alternately at each pole. The carbon dioxide forms a great cover of snow and then evaporates again with the coming of spring in each hemisphere. When the southern cap was largest, the mean daily pressure observed by Viking Lander 1 was as low as 6.8 millibars; at other times of the year it was as high as 9.0 millibars. The pressures at the Viking Lander 2 site were 7.3 and 10.8 millibars. In comparison, the average pressure of the Earth is 1000 millibars.

More info on communications between Mars/Earth and the DSN (Deep Space Network):
- NASA's MER2004 Communications with Earth Overview
- DSN (Deep Space Network) Main Page
- Wikipedia entry on Deep Space Network

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(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

Very good, technical article making point that NASA is not altering colors on Mars (beyond normal minimal adjustments to generate color images, of course).

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(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

Take a look: More info and pictures of Fulgurites on Earth .

They look exactly like that thing on Mars.

BTW, Fulgurite reminds me of the Wizard's bad-ass "F" spell in Ultima 3 (Fulgar). ;-)

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• Info (src: Athena)
• Tech Briefing (PDF 52 KB)
• Info (src: Planetary Society)
• Info (src: NASA)
• Info (src: Caves of Mars).
• Filter Specs (showing approximate color swatches in browser).

• Info (src: Athena)
• Tech Briefing (PDF 52 KB)
• Info (src: Planetary Society)
• Info (src: NASA)
• Info (src: Caves of Mars).
• Filter Specs (showing approximate color swatches in browser).

The final defining moment was when NASA, in desperation to see their only remaining project saved, went to the Air Force for its blessing. NASA asked that the AF place all of their future launches on the shuttle instead of their current expendable launchers (like the Titan II), in return for which they would no longer have to continue spending money upgrading those designs -- the shuttle would provide more than enough capability.

The Air Force relucantly agreed, but only after demanding a large increase in capability to allow for launching their projected spy satellites (mirrors are heavy). These were quite large, weighing an estimated 40,000 lbs, and needed to be put into polar orbit, which requires more energy to get to than the more common low Earth orbit. And since the AF also wanted to be able to abort after a single orbit (as did NASA), and land at the launch site (unlike NASA), the spacecraft would also require the ability to manuver significantly to either side of its orbital track to adjust for the launching point rotating away from it while in polar orbit - in a 90 minute orbit Vandenberg would move over 1,000 miles, whereas in a "normal" equatorial orbit NASA needed the range would be less than 400. This large 'cross-range' capability meant the craft had to have a greater lift to drag ratio than originally planned. This required the addition of bigger, heavier wings.

[and the next several paragraphs...]

Very interesting post. Here's my take, very rough and unchecked.

Considering that we're talking about a potential 4-hour trip, I don't think we can look back 50,000 years for the distance. Right now, we're at a 10 light-minute distance between Earth and Mars, which works out to 1.8e11 m (or 180 million km), slightly 3x what you used. This calc is from: 1. d=rt; 2. d=ct; 3. d = (3e8 m/s) x (10 min) x (60 s/min).

Next, I'll calc how long to get to the halfway point, which is 9.0e10 m away. Using 1. d=(at^2)/2; 2. t=sqrt(2d/a); 3. t = sqrt(2 x (9.0e10 m) / (9.8 m/s^2)); We get t=1.355e5 s (135000 s), or 37.646 hours.

Doubling that for the full trip is 75.29 hours, or slightly over 3 days.

So I can say, we both got the same order of magnitude (several days), but for some reason the calculations are off. I figured the distance further but got a shorter trip... Can a third party verify one of these calculations please?

And as a quick check for validity of Newtonian calcs, assume constant speed travel in this time over this distance, and check what velocity would be roughly. Calc with 1. v=d/t; 2. v=(1.8e11 m) / (1.355e5 s); 3. v=1.3284e6 m/s. Compared to speed of light (c=3.0e8 m/s), this is, as you said, less than 1%. Newton rules here.

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(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

This (one way trip to Mars) has been discussed extensively in previous /. article.

I'm all for it, and there are many smart, sane, competent people who would make a good first team and die with dignity and honor. How sad it is that in modern western society we've elevated the individual human life to such an extent that we cannot see this...

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Instead, we invested nearly everything into the Shuttle, which IMO has been a major diversion, as well as a money pit. The Shuttle is an amazing machine, but it still boils down to basically being a high-tech glider which can withstand re-entry (sometimes!).

For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

The data rate direct-to-Earth varies from about 12,000 bits per second to 3,500 bits per second (roughly a third as fast as a standard home modem). The data rate to the orbiters is a constant 128,000 bits per second (4 times faster than a home modem). An orbiter passes over the rover and is in the vicinity of the sky to communicate with the rovers for about eight minutes at a time, per sol. In that time, about 60 megabits of data (about 1/100 of a CD) can be transmitted to an orbiter. That same 60 megabits would take between 1.5 and 5 hours to transmit direct to Earth. The rovers can only transmit direct-to-Earth for at most three hours a day due to power and thermal limitations, even though Earth may be in view much longer.

This is another good source of images, here organized by date. It doesn't have all the raw images, but it has all of the press release images and some extra ones on top of that. Generally images get posted here several hours before they are attached to press releases.
JPL MER2004 Image Archive
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For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

I wonder what cpu is used on the rovers..

They use a radiation-hardened RAD6000 32-bit RISC chip made by BAE Systems. See their Press Release here. Bookmark the page in the link below.

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(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

Can anyone explain to me why all the pictures look like they're taking through a fisheye lens? Why couldn't they have used a better camera?

The pancam has a field of view similar to a human being. It is 16.8 deg x 16.8 deg (0.293 x 0.293 radians).

The navcam has a wider field of view for use during driving, and to look at the immediate surroundings. It is 45 deg x 45 deg (0.79 x 0.79 radians).

You are seeing pictures from both of these cameras, because they are using both of these cameras. The navcam gives the appearance of a "fisheye" lens. The Pancam is in fact an extremely sophisticated and detailed digital camera, and it has two eyes to create stereoscopic (3D) images that make you feel like you're on Mars. Wait a few days and you'll see some more of these images. Click the link below to see some of the good ones from Spirit.

P.S. Anybody know how to make a degree symbol in a slashdot post?

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The Pancams have two "eyes", as you noticed. Each has its own unique set of filters. Read more about the Pancam here.

The reason you are seeing mostly single shots now is because they are doing a lot of "real work" at the same time as streaming back pictures, and they need to conserve bandwidth and battery, as well as keeping the commands simple for now until they can run full diagnostics.

Another poster already mentioned it, but check out Hazy Hills Opportunity Stereo Images. It's nicely arranged for eye-crossing stereoscopic fun. There will be many more to come, but they're just getting started now.

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(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

FYI, that picture is a computer rendering of Mars, "created using Bryce and MOLA topographic data from NASA" (info here). Which is not to take anything away from it, because it's a stunning image, but let's not try to pass it off as a real photographic image.

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Try here.
Interesting that you threatended to use FOIA before actually trying to find out what's already on the web. To sum: they're using VxWorks with a radiation-hardened RAD6000 32-bit RISC chip from BAE systems. I've seen information on the RAM configuration, especially since they began having trouble with the Flash RAM; essentially, they use EEPROM, some Flash, some regular ECC RAM.

Even more here.

Go to your Slashdot Preferences, click on Comments tab. Or just click here.

You can adjust the modifiers for all adjectives. The default is 0 (which is +1 for positives and -1 for negatives), but you can, e.g., make Funny == -4.

I don't recommend it, though, because then you might miss funny Mars cartoons like this one.

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For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

• NASA Info on Pancam
• Athena Pancam Info
• Athena Pancam Technical Briefing
• Planetary Society Pancam Info

Not sure if all Aerogels are created equally, but this is from 1999 NASA article on Aerogel:
"A single one-inch thick windowpane of silica aerogel is equivalent to the insulation provided by 20 windowpanes of glass (R-20 insulation factor)."

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(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

Very good Aerogel FAQ.

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(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

• It is 99.8% Air
• Provides 39 times more insulating than the best fiberglass insulation
• Is 1,000 times less dense than glass
• Was used on the Mars Pathfinder rover

The RAT is a diamond-tipped grinding tool capable of removing a cylindrical area 4.5 cm in diameter and at least 0.5 cm deep from the outer surface of a rock. This operation takes about 2 hours for a dense basalt.

The rover has a top speed on flat hard ground of 5 centimeters (2 inches) per second. However, in order to ensure a safe drive, the rover is equipped with hazard avoidance software that causes the rover to stop and reassess its location every few seconds. So, over time, the vehicle achieves an average speed of 1 centimeter per second.

In fact it is approximately 10 minutes there and 10 minutes back. Here's how to find out. Go to John Walker's Orrery to find the current planet positions. Mars is indicated at 1.257 AU from Earth. Since we know one AU (Sun to Earth) takes about 8 min, then 8 x 1.3 = ~10 min. Check it out yourself, it's a great tool.

For this and more, check out the link in the sig below.

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(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

Anybody know what OS the rover uses?

MER2004 Mars Rovers use an OS by Wind River. Read about it at that link (press release).

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With all those links, you'd think maybe a Hubble link would surface... Here's a couple good ones:

Hubble For General Public
Hubble For Scientists
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If there had to be a compelling economic argument for everything we do we'd still be living in caves!

OK you already got ripped into a few times for this statement, but let me actually give a link where you can read some more about this issue. Robert Wright (author of book Nonzero) (who also happens to have a website of the same name) makes a very powerful argument that every advancement in cultural evolution and science in our history as a species has been as a result of the games (as in Game Theory games) we play. Zero-sum games where I take something from you, and Nonzero-sum (i.e. positive sum) games where we cooperate and advance our common cause. Anyway, I can't do it justice in a few sentences, but it's a great book and well worth the read. At the very least, poke around the website (above).

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anyone that matched orbits with your bus could just coast along and end up the same place that they would have without the bus.

Yes, but I think his point was that the tiny little ship you'd launch from Mars to catch the bus would be tiny, just to get to the bus: seats, pressure lock, enough fuel to escape gravity. Then the bus is HUGE, with a food supply, water purification system, gift shop, Mexican restaurant, arcade, and all the other things that make a 7+ month journey workable for humans. It's quite a good idea in fact.

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But they wouldn't sound anything like real sound, the pitch would be way off (kind of like hearing a sound underwater, but backwards)

Then I hope the Martians don't start playing their subliminal messages to our little rover:
"... woN tcurtseD fleS ... sretsaM dnuobhtraE ruoY nodnabA"

But seriously, here is NASA's page listing the Rover Instruments. No microphone. And for lots more info, check the link below.

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For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

For lots more info on the Pancam, other instruments on the rovers, and tons more history, news, status updates, video, 3d photos, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

High quality images are good for PR, but what I really want to know is how it extracts information from the environment, how this information is being used, and whether or not we found anything we didn't expect to find.

Another poster responded with some good details about the CCD cameras, but I think your question might be a bit more general... The MER Spirit has a very sophisticated set of scientific instruments on it, among which is the Panoramic Camera ("Pancam") which has returned many of the pretty high res photos we've seen, some in 3D.

It also has a Mini-TES (Thermal Emission Spectrometer), Microscopic Imager, Spectrometer, and lots more tools and instrumentation aboard.

A good starting point to find out more about the rover and instrument technology is:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.

For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH).

There is the "Magic Carpet" which is the odd deformation of soil left after the airbag was retracted back under the lander to clear the way for the rover. This is right next to the lander.

Further out, there are numerous marks where the lander bounced during its landing stage and the airbags deformed the soil from impacts.

So basically, as far as I can tell, all the markings are from the airbag, either bouncing or scraping on the surface.

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These rover updates are BY FAR more newsworthy than the latest Scott Peterson updates that seem to come in every couple of days on nearly all major news outlets.

Updates on the progress of the rover are NEW, and they are NEWS. I completely understand if you don't find it interesting, but in that case why do you click on the headlines, read the stories, and post about them? Just ignore them.

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For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH).

For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH).

But why does it take so long for things to retract, the rover to move, etc etc.

OK, this is a fair question. Here are four big reasons.

1. As soon as it disembarks, there are hundreds of new risk factors that come up. So they want to make sure that if anything fails (e.g. airbag catches a wheel and knocks it over, breaking off the high gain antenna), at least they've gotten something for their incredible effort.

2. They ARE conducting scientific experiments while it is safely on the lander. It is furthermore slightly elevated and able to take panoramic photos from a position it will not again regain when on ground level.

3. Getting off the lander is DELICATE. There is a ~10 minute communications lag, which means ~20 minutes to give a command and see the results. This means everything must be done very carefully and very cautiously to make sure each minor step went off perfectly.

4. If they did it quickly and something broke, every "genius" on the internet would be saying how stupid NASA was for rushing ahead and how they never get anything right and were just trying to get publicity and blah blah blah blah blah. So let them do it the right way so the mission is a success.

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For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH).

For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH).

This has links to tons of great information, images, QuickTimeVR, 3d images, videos, history, cartoons, and lots more about Mars and this MER Spirit mission in particular. Great as a springboard to look up more info as these issues (mud, water, etc.) come up.

I've been looking around various sites, but mostly keeping up with news about Spirit through google news. What is THE best site for up to the minute reports?

For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH).

This site has TONS of great links, animations, movies, cartoons, news, and everything else. I hit it and branch off from there many times a day.

It would be the same kind of murder that happens between drug dealers and gang members who hang out on the street. Somebody gets shot, then everybody runs away, and nobody is willing to be a witness.

Call it "murder", "retaliation", "brutal gangland slaying", or whatever you want, but it will happen at some point, and nobody gives a shit about whether it's legal or not, because you're talking about underground activities that have shed that distinction in order to exist and be profitable.

For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH)

every hardcore camper buys hightech gortex jackets, microfiber sweat wicking thermals, reverse osmosis water filters, carbon fiber tent poles. And silicone based lube so they can get fucked in the ass by a wandering bear.

what exactly about space exploration is going to make the earth better than it is now? Only a tiny tiny percentage of the population will be able to afford to leave Earth.

I definitely agree that the mosaics are a bit rough, but I'd *much* rather see a rough mosaic *today* than a polished one two weeks from now. I have faith that we'll get both.

For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH).

Look under "3-D glasses, sources" on the page below.

For news, status, updates, scientific info, images, video, and more, please visit: Mars Exploration Rover Highlights (AXCH).

For news, status, updates, scientific info, images, video, and more, check out:
Mars Exploration Rover Highlights (AXCH).

This has links to tons of great information, images, QuickTimeVR, 3d images, videos, history, and lots more about Mars and this MER Spirit mission in particular. I have been obsessively checking this page and branching out from there every couple of hours for the last few days.

• history on ALL past Mars attempts (those poor soviets...)
• *many* JPL and NASA pages, diagrams, videos, and photos
• info on sterescopic photos
• Sterescopic layout of Spirit's first round of photos
• Quicktime VR of the Spirit's panoramic view
• etc.