Post by Chicago Astronomer - Astro Joe on Nov 9, 2005 19:45:05 GMT -6
Simulations Show Liquid Water Could Exist on Mars
Fayetteville AK (SPX) Nov 10, 2005
University of Arkansas researchers have become the first scientists to show that liquid water could exist for considerable times on the surface of Mars.
Researchers have debated whether or not liquid water could exist on the surface of Mars because of the low temperatures and pressures found on the planet. Based on previous experiments and hypotheses, scientists have speculated that pure water on the planet's surface would evaporate from solid to gas, bypassing the liquid phase, at the low pressures found on Mars - 7 millibars as opposed to about 1,013 millibars on Earth.
However, the planet's surface sports features like gullies and channels that look as though they might have been created by the movement of liquid. Terrestrial experiments designed to simulate Mars-like conditions have been performed to help answer this question of whether or not liquid water exists on Mars, but until this point they have only been done with pure water at high pressures.
"There's a huge decrease in the evaporation rate the colder it gets, more than anyone realized," Chittenden said. With the dissolved sodium and calcium in the water, the freezing point for the brine mixtures drops to 21 degrees below zero Celsius for salt water and 50 degrees below zero for water containing calcium chloride.
Temperatures on Mars vary between 125 degrees below zero Celsius and 28 degrees above at different latitudes and different times of the day. Thus, there is a possibility that liquid water could exist on the planet's surface at different locations and times of day.
More here: www.spacedaily.com/news/mars-water-science-05q.html
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Yep...won't be a surprise to me...
