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Whirlwinds on Mars, From the Ground
Neil Halelamien writes "Back in 1999, satellite images were photographed of 5-mile-high whirlwinds streaking across the surface of Mars. A couple of months ago the Spirit rover got a close up view of whirlwind tracks, and this past week photographed a whirlwind in action (animation). It's thought that these dust devils may be responsible for the mystery power boost to the rovers' solar cells. Last year the rovers also spotted clouds and frost."
Actually, it won't tell us anything about how common they are until they snag a picture of another one :)
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
"Now we're assuming they're cleaning, but all we can really say is that overnight the solar panels produced between 2 and 5 percent additional power immediately,'' he said. "We're surmising that for some reason dust is being removed from the solar panel and that's increasing the efficiency of the sunlight being converted to electricity."
Any hardcore space-geeks care to propose any other explanation?
Seriously, i'm just wondering what else might explain this, because enough moving atmosphere on Mars to clean the panels is very interesting to me. Other possibilities anyone?
Will the next batch of rovers be equipped with windsocks, to measure the direction of the wind?
And what do you call those spinning things to measure airspeed? The ones with four arms with little hemispheric "cups" that catch the wind. KnowwhatImeanVerne?
It's not offtopic, dumbass. It's orthogonal.
For a long time, I've believed that for Humanity to survive, we *MUST* have colonies on more than just Earth. We have the technology to kill everything on this planet in minutes, and it takes a mistake by one person to start that chain of events. Maybe through our own greed and industrialization, we've already set the earth on a fatal spiral through pollution. There are also other events that can happen, which are on more of a sci-fi scale. What if the sun goes super nova? What if a giant asteroid crashes into the earth?
I'm all for spreading colonies, but your last two examples are a little more realistic than "sci-fi." We know that the sun's going to die; it'll take 4.5 billion years, but it will definitely happen. And a large asteroid will almost certainly strike the Earth. One killed the dinosaurs, and that was only 65 million years ago (a blink of an eye in the history of the Earth).
lasindi
I have discovered a truly remarkable proof of this theorem that this sig is too small to contain.
Overnight? While parked and sleeping?
Here it is without the spoilers (I don't give a shit about Star Wars, so don't bother thanking me for picking them out):
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NASA is somewhat concerned about Martian dust devils and it's impact on future human missions to Mars. There have been at least two expeditions to the Arizona desert by NASA people to study dust devils, both run out of the University of Arizona. I had the opportunity to spend a month in the Arizona desert gathering data on the second trip.
I wouldn't say that NASA is particularly concerned about dust devils -- due to the lower gravity, dust devils on mars would be much weaker than those on earth, even if they are larger. Even on earth, dust devils post little threat. Some of the ones we studied were over 2 miles tall, and you could walk right through them with absolutely no danger. While the original trip was sponsored by the HEDS funded Matador experiment to see if the dust devils posed any danger to human exploration, the primary concerns were over static electricity and dust getting into space suits.
What NASA is really interested in is how dust affect the geology of the planet. In the absense of water or strong winds, dust devils may in fact be the primary erosive force on Mars. During the first half of the 20th century, astronomers noticed that Mars changed color depending on the season, and this led them to beleive that there was rich vegetation on Mars. When the first orbiters and lander arrived, we learned that this wasn't quite true, but we still had no other solution. Now, scientists believe that is was dust devils, which are a seasonal occurance, that were actually reconfiguring the landscape of the planet. We have actually seen pictures of light colored planes that are crisscrossed by dark dust devil trails.
The problem is that very little is known about dust devils on Earth. I only know of one scientific paper published on the subject. While some of the work we did was trying to find out the proerties of dust devils, especially the electrostatic properties, to help create an accurate model for their formation on Mars, this was not really why we were there. The primary goal of the NASA researchers was to study the dust devils on earth in order to learn how to study them on Mars. We were mainly out there to test a set of instruments planned for Matador (including some far out stuff, like using a special UV camera to detect sparks caused by static electricity).
Why anyone would go to the trouble of digging up my http://science.slashdot.org/comments.pl?sid=98777& cid=8427936year old post on dust devils and then insert Star Wars spoilers into it is completely beyond me. Bonus points for remembering my post, but several thousand negative points for the plagarism and spoilers.
Actually, it won't tell us anything about how common they are until they snag a picture of another one :)
They can count the darkened dust trails from orbit. In fact, they caught some in progress from orbit. You see a dark trail that ends in a whitish puff IIRC. If they monitor an area from orbit over months or years, they can get a better estimate of the change rate. Plus, if it was a dust devil that cleaned the panels, that is another "hit". And, Pathfinder imaged one also.
Table-ized A.I.