This image of Mars's south polar region and it's ice was snapped by the Viking Orbiter (Image: NASA)
Posted on 03/17/2006 6:52:12 AM PST by S0122017
Big new reservoir of water ice suspected under Mars 13:54 16 March 2006 NewScientist.com news service Maggie McKee, Houston
Mars Express, ESA MARSIS, ESA Thomas Watters, National Air and Space Museum
A large and previously unknown reservoir of water ice may have been found below the surface of Mars, new radar observations suggest.
Gaping canyons and river-like channels attest to the fact that large amounts of water once flowed on Mars. But today most of that water has disappeared, and finding out where it went is one of the main aims of research on the Red Planet.
Scientists are using the radar antenna onboard Europe's Mars Express spacecraft as a divining rod to scout for any water that may have seeped underground.
MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) works by sending out pulses of radio waves from its main, 40-metre-long antenna and analysing the time delay and strength of the signals that bounce back. Radio waves that penetrate the surface rebound when they encounter a subsurface boundary between materials with different electrical properties – such as rock and water.
The antenna was deployed in June 2005 and quickly detected what appeared to be water ice stretching 1.8 kilometres below the surface of the northern polar ice cap. Now, it has found what looks like water ice extending as deep as 3.5 kilometres below the southern polar cap.
Global matrix Water ice was expected in the polar caps, since they represent the largest known reservoirs of water on Mars. Estimates suggest that if they melted, they would cover the planet in a layer of water up to 33 metres deep.
But as it scanned the region around the south pole, MARSIS also turned up an unexpected ice source. It lies near the southern polar cap and is underneath a region of Martian surface that shows no visible signs of ice. The radar signals reveal what appear to be relatively thin layers of underground water ice – layers that may contain water of a equivalent to half of that locked up in the entire southern polar cap.
"If we can confirm the thinner layers are, in fact, ice rich, we've put our finger on another reservoir of water that is significant in the global water matrix," says MARSIS co-leader Jeff Plaut of NASA's Jet Propulsion Laboratory in Pasadena, California, US. He presented the new data at the Lunar and Planetary Science Conference (LPSC) in Houston, Texas, on Monday.
He says the interpretation of the radar boundaries as layers of ice is bolstered by the fact that they are so near the confirmed ice in the polar cap, but he cautions that the signals could simply be layers of dust.
If they are actually water ice, they may shed light on the planet's past climate. The polar ice caps themselves are made of icy layers that researchers believe were laid down as snow during periodic swings in the planet's tilt – and therefore its climate – every 50,000 years. Plaut says studying the shape and thickness of the layers could reveal more about the nature of these climatic shifts.
Lava resurfacing And MARSIS is already rewriting how researchers interpret Martian history. It has revealed about 10 buried impact craters – some as wide as 470 kilometres – in the planet's northern lowlands. Only one of these craters is visibly detectable on the planet's surface.
That is important because researchers date Martian surfaces by counting the number of craters embedded within them. The planet's northern lowlands show relatively few craters, while the southern highlands are pockmarked by impacts. That had long suggested that the northern lowlands had been resurfaced by lava and were thus younger than the southern highlands.
But recent orbital observations with a laser altimeter have challenged this conclusion. The altimeter revealed some craters whose rims had eroded so much that they were undetectable by sight, suggesting these surfaces were actually older than they appeared.
The new MARSIS data further supports this idea, says Thomas Watters at the National Air and Space Museum in Washington DC, US, who led the team that discovered the buried craters. "It suggests there is only a small age difference between the highlands' and lowlands' crust," he said at the LPSC meeting.
This image of Mars's south polar region and it's ice was snapped by the Viking Orbiter (Image: NASA)
Mars Ping
I think the biggest obstacle on Mars will be the radiation from space. That would force us underground but that may not be a bad thing.
It once SNOWED on Mars......
Now really. I'm not planning a trip next week or next year for that matter. WRGARA.
:)
okay
everyone here keep on clapping
keep your hands high, where I can see them
so who stole the water?
Ski Trip!
With the size of those mountains and the lower gravity, if we could get it snowing again what a ski resort it would make!
TM
Eminent domain by God.
From a tiny spec of ice like that?
It's too cold on mars to ever melt ice and make flowing water, plus it will only evaporate and escape to space and break down into it's elements anyways.
Well, not so sure. The suspected reason Mars has little atmosphere or water vapor is that with no magnetic field, it all sublimated off into space eons ago. Whats left is in frozen state in the ground where it is somewhat shielded from the same fate. If you start trying to create an atmosphere with water vapor from the ground source, the same thing will probably occur. We really cant do much about the lack of a Mag field on Mars.
The article states:
Gaping canyons and river-like channels attest to the fact that large amounts of water once flowed on Mars. But today most of that water has disappeared, and finding out where it went is one of the main aims of research on the Red Planet.
The writer is not well informed. The large canyons visible from Earth are not from water flow. They are there because the crust 'crumbled' as the planet cooled. Mars has no mag field because its once molten core is now cold and solid. No moving magma, no resulting currents and mag field.
So terraforming may be much more difficult that supposed. Thats my understanding of the current theories anyway. I am not an expert on this, but its related to my area.
"So terraforming may be much more difficult that supposed. Thats my understanding of the current theories anyway. I am not an expert on this, but its related to my area."
It isn't so much the lack of magnetic field as it is simply the lower gravity. Both have an effect though.
My understanding has been that Martian terraforming would be "temporary" in the sense that the native atmosphere/water might only last a "few" million years. I guess the thinking is that by the time the atmosphere noticeably thinned we'd be able to bring in raw materials from just about anywhere. ;-)
Heck, within even a thousand years I'd expect mankind to have the technology to re-melt the Martian core if we felt like it.
It's no the lack of a magnetic field that makes radiation from space dangerous nor the reason why it would be difficult to terraform Mars. A thick atmosphere protects us on Earth from space born radiation. Protection from a magnetic field depends upon polarity of the radiation. The atmosphere is far more effective. Also, if we wanted to warm up Mars, the desired temperature would dictate, via the Boltzmann distribution of temperature dependent molecular velocities, a situation where there would be a significant number of velocities greater than escape velocity for Mars, which has lower gravity than the Earth. If the Earth had the mass of Mars, we would have no atmosphere because we are much warmer. At least Mars can hold onto a tiny fraction of our atmosphere because it is so cold.
duh, mhmmmmm, lets try that again
so he took it and moved it to earth?
Nope.....He told me He took it to that moon around Saturn.....
:^)
I think there are some feats that are reserved for God. I dont think man will have the ability to do this, not before blowing himself up first, unfortunately. Besides, if the enviro whackos survive, they would never permit something like that. I am sure they would find a Martian slug worm that would be harmed.
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