Posted on 03/15/2007 1:01:58 PM PDT by Pharmboy
A spacecraft orbiting Mars has scanned huge deposits of water ice at its south pole so plentiful they would blanket the planet in 36 feet of water if they were liquid, scientists said on Thursday.
The scientists used a joint NASA-Italian Space Agency radar instrument on the European Space Agency Mars Express spacecraft to gauge the thickness and volume of ice deposits at the Martian south pole covering an area larger than Texas.
The deposits, up to 2.3 miles thick, are under a polar cap of white frozen carbon dioxide and water, and appear to be composed of at least 90 percent frozen water, with dust mixed in, according to findings published in the journal Science.
Scientists have known that water exists in frozen form at the Martian poles, but this research produced the most accurate measurements of just how much there is.
They are eager to learn about the history of water on Mars because water is fundamental to the question of whether the planet has ever harbored microbial or some other life. Liquid water is a necessity for life as we know it.
Characteristics like channels on the Martian surface strongly suggest the planet once was very wet, a contrast to its present arid, dusty condition.
Jeffrey Plaut of NASA's Jet Propulsion Laboratory in Pasadena, California, who led the study, said the same techniques are being used to examine similar ice deposits at the Martian north pole.
Radar observations made in late 2005 and early 2006 provided the data on the south pole, and similar observations were taken of the north pole in the past several months, Plaut said.
Plaut, part of an international team of two dozen scientists, said a preliminary look at this data indicated the ice deposits in at the north pole are comparable to those at the south pole.
SEARCH FOR LIFE
"Life as we know it requires water and, in fact, at least transient liquid water for cells to survive and reproduce. So if we are expecting to find existing life on Mars we need to go to a location where water is available," Plaut said.
"So the polar regions are naturally a target because we certainly know that there's plenty of H2O there."
Some of the new information even hints at the possible existence of a thin layer of liquid water at the base of the deposits.
But while images taken by NASA's Mars Global Surveyor spacecraft made public in December suggested the presence of a small amount of liquid water on the surface, researchers are baffled about the fate of most of the water. The polar deposits contain most of the known water on Mars.
Plaut said the amount of water in the Martian past may have been the equivalent of a global layer hundreds of meters deep, while the polar deposits represent a layer of perhaps tens of meters.
"We have this continuing question facing us in studies of Mars, which is: where did all the water go?" Plaut said.
"Even if you took the water in these two (polar) ice caps and added it all up, it's still not nearly enough to do all of the work that we've seen that the water has done across the surface of Mars in its history."
Plaut said it appears perhaps 10 percent of the water that once existed on Mars is now trapped in these polar deposits. Other water may exist below the planet's surface or perhaps some was lost into space through the atmosphere, Plaut said.
Get Schwarzenegger!
He knew how to save Mars back in "Total Recall".
With an atmosphere there, we can start building vacation condos.
"We'll take Mars!"
I think it should be the other way around. Then We can laugh at them when they screw it up.
Ha! I just put the salt that was left over from the winter in the back of the garage (northern NJ) and now I have to retrieve it since we're getting a snowstorm tomorrow. Durn global cooling...er, I mean warming...oh--whatever.
Sublimation, anyone? Nobody at nasa has ever heard of Boyle's Law?
Sheez.
He was a right-wing God, after all...
Though Martin humans would be taller than Earthling humans--though weaker, too.
Not long ago. Very recently according to the Van Flandern hypothesis.
Martian.
if anyone knows why the moisture would migrate to the polar regions of the planet.
just my guess......given Mars position as relates to the Sun, sunlight must travel thru more atmosphere at the N and S poles, which decreases the heat reaching the surface, compared to its equator. Same reason the Earth's warmest temps are on the equator, LOL
Where's a latter day Velikovsky when things get interesting?
The Italian who stated that supposedly used canalli, which was improperly translated "canals," instead of the proper "channels."
Dynamic cooling. The entire planet undergoes periodic cooling and warming but the extreme poles are relatively stable. The water in temperate regions tends to evaporate and enter the atmosphere and evenly precipitate all over the planet. The water in the polar extremes tends to remain there once deposited. After the atmosphere was dissipated, the resulting deep freeze kept the status quo with the majority of water located at the poles.
The Martians better be able to withstand radiation from space too.
Uh oh! I can see it now - any further exploration of Mars is halted because of threats of "Martian Warming"...
Whyever would it "be over"?? I would think finding life on Mars (even bacterial) would BOOST the space program--not kill it.
There are plenty of so called 'progressives' out there who are opposed to any space exploration till we "fix this planet".
It's already been warmed, that's why the water ice is only at the poles now.
Well, that's because they figure they learned everything anyone could possibly need to know, sitting at the feet of their gods in college. Why should humanity need to explore further, or learn more about anything? They already know it all! Just ask them, they'll tell you!
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