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Astronomy Picture of the Day 9-03-02
NASA ^ | 9-03-02 | Robert Nemiroff and Jerry Bonnell

Posted on 09/02/2002 10:32:34 PM PDT by petuniasevan

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2002 September 3
See Explanation.  Clicking on the picture will download
 the highest resolution version available.

A Dust Devil on Mars
Credit: Malin Space Science Systems, MGS, JPL, NASA

Explanation: Does the surface of Mars change? When inspecting yearly images of the Martian surface taken by the robot spacecraft Mars Global Surveyor currently orbiting Mars, sometimes new dark trails are visible. Although originally a mystery, the culprit is now usually known to be a dust devil, a huge swirling gas-cloud with similarities to a terrestrial tornado. Pictured above, a recent image has not only captured a new dark trail but the actual dust devil itself climbing a crater wall. Dust devils are created when Martian air is heated by a warm surface and begins to spin as it rises. Dust devils can stretch 8 kilometers high but usually last only a few minutes.

TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: astronomy; climate; crater; dust; dustdevil; exploration; globalsurveyor; image; mars; orbiter; photography; redplanet; surface; terrain; weather
Astronomy Fun Fact:

Mars' carbon dioxide atmosphere is only 1% as dense as Earth's at sea level.
A 100 mph wind would feel like a light breeze, but would be blowing dust and sand.

Be sure to click on the "Martian air" link in the above article and read about the Kitty Hawk (!) project.

Get on the list!

1 posted on 09/02/2002 10:32:35 PM PDT by petuniasevan
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To: MozartLover; Joan912; NovemberCharlie; snowfox; Dawgsquat; viligantcitizen; theDentist; grlfrnd; ...

2 posted on 09/02/2002 10:33:53 PM PDT by petuniasevan
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To: petuniasevan
I saw a great one in Sisters Oregon last month. Wasn't like the wide cone shaped ones we get here in Cali. It was tall, tight and narrow. Everybody stopped to watch it.
3 posted on 09/02/2002 10:37:22 PM PDT by farmfriend
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To: farmfriend
Dust devils can be strong! When I was in junior high school in Southern California, I had an encounter with a monster duster. The whirlwind swept through the yard and nearly knocked me down. A student nearby had a notebook full of papers torn from his grasp and sent whirling up 50-100 feet and away.

On my way home that day, I saw the scattered pages from that notebook strewn through a housing tract 1/2 mile away.

4 posted on 09/02/2002 11:34:47 PM PDT by petuniasevan
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To: petuniasevan
I can believe it. This one was at least several stories tall. It only broke up after it incountered a gas station. Looked just like a tornado. Only smaller of course. I'm use to the big swirly ones that just throw a lot of dust around.
5 posted on 09/03/2002 12:09:01 AM PDT by farmfriend
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To: petuniasevan
Wow! A dust devil that is 8 kilometers? What a monster!

We lived in Mountain Home AFB, Idaho when I was a kid (Air Force Brat!). That's the desert part of Idaho (southwestern Idaho). We saw dust-devils all the time there. What I remember that was such a strange thing was living across the street from the Base Golf driving range. They had water sprinklers going all the time and it was lush green. We could walk down the street about 2 blocks or so and there was a barricade at the dead end street. Beyond the barricade? Nothing but sagebrush, sand scorpion dusty desert. It was a strange thing to see such a stark contrast on base/off base.

6 posted on 09/03/2002 5:08:37 AM PDT by MeekOneGOP
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To: petuniasevan
Looks like the ones we have here in arizona! Good job APOD!
7 posted on 09/03/2002 7:48:25 AM PDT by BossyRoofer
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To: sleavelessinseattle
Missed you last night! You shouldn't miss out on a Mars APOD!

It's not the same here without your input!

8 posted on 09/04/2002 5:10:47 AM PDT by petuniasevan
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To: petuniasevan
I was so excited by the glider concept I forgot to post how EXCITED I WAS!!! LOL!!!!!! I NEED HELP or MORE TOYS P7!
9 posted on 09/04/2002 7:37:00 AM PDT by sleavelessinseattle
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