LEAD: A year’s worth of weather data from Mars indicates conditions are favorable for small quantities of salty water (brine) to form at night at Gale crater.
1. Mars’ soil contains perchlorate salts that can pull water vapor out of the air. On cold nights when the relative humidity is high, they pull so much water that they dissolve into liquid, forming a salty brine.
2. NASA’s Mars Curiosity rover weather station shows winter daytime temperature highs of around 0 Degrees Fahrenheit. But nighttime lows are near minus 135 Degrees Fahrenheit with relative humidity at 60%.
TAG: Despite this evidence, the low temperatures and high salinity levels are likely to make the water unsuitable for life.