Martian pole capped by planet swamping ice sheet
There's ice in them thar hills
The southern pole of Mars is hidden beneath a "deep and wide" layer of ice - enough that if it melted*, it would cover the whole planet in a sea 36 feet deep. Shallow for a sea, but still a fair quantity of aqua.
The findings are published in the 15 March online edition of the journal Science. Lead author Jeffrey Plaut said: "The south polar layered deposits of Mars cover an area bigger than Texas. The amount of water they contain has been estimated before, but never with the level of confidence this radar makes possible."
The precise measurements were taken with MARSIS, a joint NASA Italian Space Agency instrument on the European Space Agency's Mars Express orbiter. The radar instrument can see through the ice to the ground below. At its deepest, this is 2.3km below the surface of the ice.
Giovanni Picardi, professor at the University of Rome, and principal investigator for the instrument commented: "MARSIS is showing itself to be a very powerful tool to probe underneath the Martian surface...the details we are seeing are truly amazing."
He added that the instrument is still to be fine tuned, and should soon be capable of producing even more detailed information on the composition of the surface and subsurface.
So far, there is one signal that has puzzled the scientists: at the base of one layer of ice, there is a particularly light reflection. The characteristics are such that if it were warmer, the team would confidently identify it as liquid water. But it so cold that liquid water is extremely unlikely, the researchers say.
These polar layered deposits hold most of the water on Mars, and extend beyond a bright white polar cap of frozen carbon dioxide. The radar pings suggest that 90 per cent of the material below the polar cap is frozen water. ®
*Not on our list of likely events, either.
Use the itrw!
El Reg should report all distances in the itrw! (Good enough for Senurset I, good enough for us.)
should be metric
"I found the use of imperial on a site which should be metric somewhat amusing and disturbing myself."
Who decided that this site should only use metric? You? The UK government? The US government?
I have no knowledge of any rule or law which states that only metric measurements should be used here.
"Disturbing"? If such a small thing as the use of feet disturbs you, perhaps you are indeed "disturbed". You seem to be some kind of metric fascist.
Metric & other spacial anomolies
I found the use of imperial on a site which should be metric somewhat amusing and disturbing myself. But here's the rub - a 'foot', metricised as a 30cm ruler, is a metric measure of convenience these days. Using miles on the other hand is just plain stupid.
Now in relation to the Blue Sky on Mars scenario, ala Total Recall, someone mentioned, there's a few things going against the Red Planet for that to happen.
Firstly, the planet doesn't have a sufficient magnetic field for a dense atmosphere and hence liquid water to form. Being a smaller body with less mass and less gravity doesn't help matters either. At some time this wasn't the case and Mars had a more dynamic climate and atmosphere. But being a smaller planetary body, it cooled more quickly than the Earth resulting in the mechanisms which create the Mars' magetic field, believed to be the turning and churning of the inner cores, slowing down or stopping all together, resulting in the field disipating and much of the atmosphere and possibly a great deal of water being lost into space, carried away by the charged particles of the solar wind. What didn't rise, sunk into the crust.
Even if you could melt these frozen oceans (and it's believed a similarly large deposit of water sits under the north pole), it would gradually or rapidly (no one is quite sure) drift off into space. Without somehow re-establishing the magnetic field, a denser and warmer atmosphere cannot form. In a thin atmosphere, liquid water quickly evaporates.
But don't take my word for it, http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=31025 .