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.
Thanks in advance for your answers...
I could easily be way wrong.
I'm not sure. I think Mars has a semi-liquid core, whereas we have a solid inner core, and a consistently liquid outer core.
I think one big difference is our big moon - it zips around us, and its gravity churns up our outer core into a nice fluid - and it's the MOVING iron that causes the field to propagate. (Think of an electric motor / generator.)
I'm not sure. I think Mars has a semi-liquid core, whereas we have a solid inner core, and a consistently liquid outer core.
I think one big difference is our big moon - it zips around us, and its gravity churns up our outer core into a nice fluid - and it's the MOVING iron that causes the field to propagate. (Think of an electric motor / generator.)
NASA to Announce 'Significant Findings' of Water on Mars Tuesday!
Space DOT com | 3-1-04 | Robert Roy Britt Senior Science Writer
Posted on 03/01/2004 5:08:45 PM EST by vannrox
http://www.freerepublic.com/focus/f-news/1088571/posts
The Yardangs of Mars
Geological Society (UK) | July 24, 2004 | staff
Posted on 01/01/2005 2:18:55 PM EST by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1312117/posts
Images reveal 'sea of ice' near Mars' equator
Associated Press | Feb 26, 2005
Posted on 02/26/2005 4:02:49 AM PST by FYREDEUS
http://www.freerepublic.com/focus/f-news/1351506/posts
It would probably condense there because of the cooler temperatures.
YEAH BABY this is GREAT HISTORIC NEWS!!!
There is life...we will find it....bacteria....worms...who knows
whats crawling around in the dirt.
We can't live on Mars....its slightly bigger than the moon...
gravity is toooo weak for us to be healthy. We can live in orbit
and come down to dig and find fossils....who knows what!!!
This is NASA's problem...their PR department SUCKS. That should have been a non-story. Instead every time there's an article about the good things that NASA is doing, Nowak creeps into the discussion.
Well for that we need heavy-lift. I.e. something on the order of the Saturn V. Which is COMING with Ares V, provided that NASA isn't messed with as far as the budget goes. As far as the pressure goes, it's not about gravity. It's about density. If we heat the planet, we release the sequestered CO2 and H2O faster than the solar wind can strip away molecules from the top of the atmosphere. Then we've created a denser atmosphere, higher density, higher mass, higher pressure.
If it were ONLY about gravity, Mars would ALREADY have an atmospehre with 1/3 the pressure of MSL on Earth, because Mars gravity is 1/3g. And the moon would have a 1/6bar atmosphere. It doesn't work that way.
Or maybe not a direct impact. The gravitational attraction of a near miss by a large rock (planet-size or nearly) could strip off almost all the water, very quickly, and leave one hemisphere of Mars very different from the other hemisphere, as it is now.
Yeah, I saw that less than an hour after I asked. Laughed when I saw it. =)
Bump for later read.
Their PR is GREAT.
Has the US press ever
described the events
around NASA's TOMS
ozone monitoring mess
caught by Forest Mims?
You've got to wonder
how much is unseen given
all the stuff we see.
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