1. DISCOVERY

    Scientists: Evidence of Saltwater on Mars

    FILE - In this file image provided by NASA's Hubble Space Telescope a close-up of the red planet Mars is shown. Two scientists are proposing we send volunteers to Mars and leave them there. They say the mission would mark the beginning of long-term human colonization of Mars, with numerous follow-up trips. The colleagues contend one-way missions could happen a lot quicker and cheaper, and it is essential to begin colonizing another planet as a hedge against a catastrophe that makes Earth uninhabitable. (AP Photo/NASA, File)

    NASA / AP Photo

    Scientists may have found signs that salt water exists on Mars, which would be one of the biggest clues yet that life possibly exists on the planet. At a NASA news conference on Thursday, they announced the discovery of dozens of slopes across the planet's southern hemisphere. When Mars gets warm, the slopes appear in the form of dark streaks that expand downhill, then the streaks disappear during the cold season, when water presumably freezes up. They believe the streaks signify a salty, syrupy-like water running on or below the planet's surface, and have counted as many as 1,000 possible streams flowing down from the planet's Newton Crater and into a basin. "If we confirm that it is a salty water, then we have the best idea yet about where to go to try to find extant life on Mars,” said the lead author of the study.

    Read it at Washington Post