skunk
06-27-2009, 05:25 PM
Mars may hide secret water table (http://www.newscientist.com/article/mg20227145.000)
Well this could be good news for those of us who live long enough to see the human race leave this planet (for better or worse).
[offsite:39znghj8]THE Red Planet could have a water table hidden underground, despite satellite data suggesting otherwise.
Today the small amount of water detected on the planet is locked in the polar ice caps, but recently discovered geological features suggest liquid water once flowed on its surface (http://www.newscientist.com/article/mg20126883.600-mystery-stone-circles-may-point-to-water-on-mars.html). This could now be hiding beneath the rocky crust.
The European Space Agency's Mars Express satellite has used ground-penetrating radar in some areas to look for a water table but found no evidence for one, despite research that concluded any water would be found within 9 kilometres of the surface - well within the reach of the probe's instruments.
Planetary scientist Bill Farrell of NASA's Goddard Space Flight Center in Greenbelt, Maryland, and colleagues will argue in Geophysical Research Letters that we shouldn't give up the search just yet, however. The satellite's radar signal should bounce back from shiny surfaces like water. But the team calculates that if the layer of rock and icy soil above the water table is particularly conductive, it could be absorbing enough energy from the radar to obscure a telltale signal.
Farrell says the work will be useful for missions to other icy bodies too: "We don't want future geologists to look at their radar data and say no reflectance means no aquifer."[/offsite:39znghj8]
Well this could be good news for those of us who live long enough to see the human race leave this planet (for better or worse).
[offsite:39znghj8]THE Red Planet could have a water table hidden underground, despite satellite data suggesting otherwise.
Today the small amount of water detected on the planet is locked in the polar ice caps, but recently discovered geological features suggest liquid water once flowed on its surface (http://www.newscientist.com/article/mg20126883.600-mystery-stone-circles-may-point-to-water-on-mars.html). This could now be hiding beneath the rocky crust.
The European Space Agency's Mars Express satellite has used ground-penetrating radar in some areas to look for a water table but found no evidence for one, despite research that concluded any water would be found within 9 kilometres of the surface - well within the reach of the probe's instruments.
Planetary scientist Bill Farrell of NASA's Goddard Space Flight Center in Greenbelt, Maryland, and colleagues will argue in Geophysical Research Letters that we shouldn't give up the search just yet, however. The satellite's radar signal should bounce back from shiny surfaces like water. But the team calculates that if the layer of rock and icy soil above the water table is particularly conductive, it could be absorbing enough energy from the radar to obscure a telltale signal.
Farrell says the work will be useful for missions to other icy bodies too: "We don't want future geologists to look at their radar data and say no reflectance means no aquifer."[/offsite:39znghj8]