The Red Planet is wet, scientists announced today. New evidence from NASA’s Mars Reconnaissance Orbiter (MRO) confirms that suspicious dark streaks on Mars that appear and disappear with the seasons are created by flowing liquid water. The streaks are made by salty water that runs down steep hills during warm months, when temperatures are above –23 degrees Celsius, and freezes during colder times.
Image: New evidence confirms that liquid water flows on present-day Mars in so-called recurring slope lineae--dark streaks on the Red Planet's slopes that appear in warmer seasons. NASA/JPL-Caltech/Univ. of Arizona
