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Naru523
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« on: July 21, 2009, 11:39:33 AM » |
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 This visualization of a gravity model was created with data from NASA's Gravity Recovery and Climate Experiment (GRACE) and shows variations in the gravity field across the Americas. Gravity is determined by mass. Earth’s mass is not distributed equally, and it also changes over time. The colors in this image represent the gravity anomalies measured by GRACE. One can define standard gravity as the value of gravity for a perfectly smooth 'idealized' Earth, and the gravity 'anomaly' is a measure of how actual gravity deviates from this standard. Red shows the areas where gravity is stronger than the smooth, standard value and blue reveals areas where gravity is weaker. GRACE is a collaborative endeavor involving the Center for Space Research at the University of Texas, Austin; NASA's Jet Propulsion Laboratory, Pasadena, Calif.; the German Space Agency and the German Research Center for Geosciences, Potsdam. More information on the GRACE mission is online at http://www.csr.utexas.edu/grace/ and http://grace.jpl.nasa.gov/. ==============================================================================  Scientists have combined a trio of shots taken seconds apart through different colored filters to create a special-effects portrait of a moving dust devil on Mars. The panoramic camera on NASA's Mars Exploration Rover Spirit was taking exposures through different filters during the 1,919th Martian day of Spirit's mission (May 27, 2009) as part of constructing a large color panorama. Three westward shots, with several seconds intervening between them, caught a whirlwind in motion. A composite image combining the three exposures to make a color image of the Martian ground shows the dust devil in different colors, according to where it was on the horizon when each exposure was taken. Dust devils occur on both Mars and on Earth when solar energy heats the surface, resulting in a layer of warm air just above the surface. Since the warmed air is less dense than the cooler atmosphere above it, it rises, making a swirling thermal plume that picks up the fine dust from the surface and carries it up into the atmosphere. This plume of dust moves with the local wind. More than 650 dust devils have been recorded by Spirit since its operations began in 2004. The mission is currently in its third season of dust devils on Mars, which typically begin in Martian spring.
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« Last Edit: July 21, 2009, 11:43:08 AM by Naru523 »
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Naru523
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« Reply #1 on: July 21, 2009, 11:55:05 AM » |
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It could be possible, that asteroids or comets wouldn't hit blue parts, but may hit green/red parts  |
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Bla
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« Reply #2 on: July 21, 2009, 11:57:37 AM » |
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NeutronStar will love this. Now, which of them should we name Alpha, Beta, Gamma, Delta and so on...?  |
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atomic7732
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« Reply #4 on: July 21, 2009, 01:47:58 PM » |
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Lol, ya know I saw this before any of you commented on it. Btw, I think it's one dust devil. If not, then you would have: Alpha, Beta, Gamma, Delta, Epsilon, and Zeta. |
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« Last Edit: July 21, 2009, 01:54:07 PM by NeutronStar »
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monmarfori
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« Reply #5 on: July 21, 2009, 02:53:21 PM » |
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Really in the top picture was hypotetically colored dust devils!
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atomic7732
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« Reply #6 on: July 21, 2009, 03:08:35 PM » |
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Really in the top picture was hypotetically colored dust devils!
No their not. Quoted as above by Naru523: Scientists have combined a trio of shots taken seconds apart through different colored filters to create a special-effects portrait of a moving dust devil on Mars.
The panoramic camera on NASA's Mars Exploration Rover Spirit was taking exposures through different filters during the 1,919th Martian day of Spirit's mission (May 27, 2009) as part of constructing a large color panorama. Three westward shots, with several seconds intervening between them, caught a whirlwind in motion. A composite image combining the three exposures to make a color image of the Martian ground shows the dust devil in different colors, according to where it was on the horizon when each exposure was taken.
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Dan Dixon
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« Reply #7 on: July 21, 2009, 04:51:13 PM » |
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It could be possible, that asteroids or comets wouldn't hit blue parts, but may hit green/red parts Probably not... While it is true that "Earth’s mass is not distributed equally" the difference between the red and blue parts of the image are very small and certainly not enough to change the trajectory of an asteroid on a collision course with Earth. In Universe Sandbox all bodies are calculated as single point masses and as perfectly spherical bodies (which isn't how planets and stars are really shaped). |
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atomic7732
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« Reply #8 on: July 21, 2009, 05:02:56 PM » |
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They are roughly!
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monmarfori
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« Reply #9 on: July 21, 2009, 08:46:05 PM » |
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Why?
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Bla
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« Reply #10 on: July 22, 2009, 12:44:48 AM » |
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Just think about it. It looks like the gravity is stronger at the mountains and lower in the deep sea. So it may not be any special heavy materials under the surface. The Earth is many thousand kilometers in diameter, but the mountains are max 8, and the deepest sea 11 km under the surface covered with water. I doubt these -11 or +8 km will add much gravity to the thousands of kilometers our Earth is thick, also it's visible that the terrain is made much more "strong" on the picture.  In real life, Earth is a sphere. |
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monmarfori
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« Reply #11 on: July 22, 2009, 01:08:53 AM » |
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But really colored dust devils may be rare.
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Bla
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« Reply #12 on: July 22, 2009, 01:56:48 AM » |
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But really colored dust devils may be rare.
They're colored relative to their distances in the horizon when each exposure was taken: The panoramic camera on NASA's Mars Exploration Rover Spirit was taking exposures through different filters during the 1,919th Martian day of Spirit's mission (May 27, 2009) as part of constructing a large color panorama. Three westward shots, with several seconds intervening between them, caught a whirlwind in motion. A composite image combining the three exposures to make a color image of the Martian ground shows the dust devil in different colors, according to where it was on the horizon when each exposure was taken. |
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monmarfori
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« Reply #13 on: July 22, 2009, 04:59:22 AM » |
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Is that really a tornado?
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Naru523
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« Reply #15 on: July 22, 2009, 11:08:01 AM » |
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Wow, they're almost as large as Himylayas...
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atomic7732
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« Reply #16 on: July 22, 2009, 11:14:58 AM » |
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Theyr'e not tornadoes, they're dust devils.
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monmarfori
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« Reply #17 on: July 22, 2009, 02:29:07 PM » |
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A dust devil is a tornado that forms in deserts.
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hbmp88
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« Reply #18 on: July 22, 2009, 02:37:33 PM » |
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A dust devil is a tornado that forms in deserts.
A dust devil does not extend from a cloud, and is therefore more weak. You would be lucky to find a tornado in clear air. and... Dust devils are drafts. Tornadoes occur when high pressures collide with low pressures. |
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atomic7732
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« Reply #19 on: July 22, 2009, 02:45:27 PM » |
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close, but they are formed when hot air it trapped below cold air, The warmer air breaks through making a vortex of cold air downdrafts and warm air updrafts, creating a cyclonial shape and (possibly) picking dust or leaves off of the ground.
Monmarfori, they aren't tornadoes. They would just be called tornadoes. Tornadoes for in supercells, a strong type of thunderstorm.
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hbmp88
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« Reply #20 on: July 22, 2009, 03:39:50 PM » |
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close, but they are formed when hot air it trapped below cold air, The warmer air breaks through making a vortex of cold air downdrafts and warm air updrafts, creating a cyclonial shape and (possibly) picking dust or leaves off of the ground.
That is called a draft. A draft is when warm air go up and WEEEEEEEEEEEEEEE cool air heavy go down to ground.  |
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atomic7732
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« Reply #21 on: July 22, 2009, 04:26:02 PM » |
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Well, I didn't know! |
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monmarfori
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« Reply #22 on: July 22, 2009, 08:45:10 PM » |
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Some future dust devils. may be stronger because of desertification.
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atomic7732
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« Reply #23 on: July 22, 2009, 09:59:36 PM » |
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that has nothing to do with it, they can happen anywhere... with dirt!
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monmarfori
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« Reply #24 on: July 23, 2009, 01:25:11 AM » |
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Because desert is growing all in the world.
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Bla
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« Reply #25 on: July 23, 2009, 02:13:00 AM » |
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But that doesn't make them stronger I guess. I mean, if Sahara grows by 100 km and a dust devil occurs in the middle, the growth will have nothing to do with it.
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hbmp88
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« Reply #26 on: July 23, 2009, 11:15:24 AM » |
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I see dust devils at my school! I must live in hot hot desert. NOT
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monmarfori
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« Reply #27 on: July 23, 2009, 02:19:38 PM » |
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Are you living on the desert?
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hbmp88
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« Reply #28 on: July 23, 2009, 03:02:00 PM » |
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NO
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Naru523
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« Reply #29 on: July 23, 2009, 03:56:49 PM » |
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Psss... Their's no desert in California... except Death Valley. |
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