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Ice Lake on Mars
DecoDragon writes "The ESA's Mars Express discovered an ice lake on Mars. The ESA has a number of images and an explanation of what was found. The lake was found in an unnamed crater. The report says it can't be carbon dioxide, because carbon dioxide ice had already disappeared from the northern polar cap at the time the image was taken." Coverage from the BBC also available. From the article: "The team has also been able to detect faint traces of water ice along the rim of the crater and on the crater walls. Mars is covered with deep gorges, apparently carved out by rivers and glaciers, although most of the water vanished millions of years ago. "
Excerpt taken from a chat session between ESA and NASA lead engineers: NASA: "Our Mars Rovers are both still going strong, moving at over an inch per day, and finding all sorts of great new types of reddish sand. I could possible arrange to send you some sam-" ESA: "WATER!! YEAH BABY!! WE pWnEd j0000!!! MWA AHHAHAHAHAH!!"
Romance advice authors have found evidence of men on Mars. No word on Venus.
See the phase diagram for water Here
It'd be nice if there was some more marks on the axes, but you can see that somewhere below one atmosphere of pressure, you can get directly from ice to vapor.
If I have been able to see further than others, it is because I bought a pair of binoculars.
On Earth, where there be water, there be life.
And where there be water, there be pirates. Yarrrr!
I watched C-beams glitter in the dark near the Tannhauser gate.
I would agree with you, but I think that you assume a surface pressure of only 1 Pa. At the recorded pressures of 0.675-1 kPa for Mars' atmosphere, water remains ice until it reaches a temperature of somewhere between 240 to 275 K (-27 to 35 F). The average recorded temperatures of the surface of Mars ranges between 130-250K (-225 to -9 F) with a mean of 210K, so it is entirely possible for this ice to remain year round without sublimating, or melting at the extreme temperature (275K) and pressure (1 kPa) range. I am only extrapolating these values from a phase diagram for water, therefore the numbers are most likely off. This, of course, also assumes that the sun is not shining on the region in question, as soil temperatures of 300K (+81 F) have been reported.
"When Nature Calls We All Shall Drown" Johan Edlund
It's pretty clear that life requires a solvent of some kind to form the complex molecules needed for life. Try and imagine amino acids forming in ice or some other solid. Water is regarded as the universal solvent since virtually everything will dissolve in it. Add to that that water is pH neutral and it provides a very hospitable environment for these molcules.
Also, water has the unique property of being less dense in solid form than liquid form, hence ice floats. Thus, when bodies of water freeze, the ice settles on top of it. In other words, water freezes from the surface down, unlike other liquids. This action provides an insulating layer which allows life to flourish under the surface instead of being driven to the surface by ice forming from the bottom up.
Water also has strong surface tension due to the hydrogen bonding between water molucules. This allows for capillary action in which plant can pull water up against gravity. This isn't necessary for the formation of primitive life, but it's difficult to imagine higher forms of life without it.
No, all science points to water being the one molecule which is able to nurture and sustain life. It's an amazing compound despite the fact that it's so prevalent that we tend to take it for granted.
"War is God's way of teaching Americans geography." -- Ambrose Bierce