Remember the "recurring slope lineae?"
Nope? How about "liquid water on Mars"?
That should ring a bell. In the fall, NASA scientists announced the strongest suggestion yet that the Red Planet may occasionally host patches of liquid water. These "recurring slope lineae" (RSL) appear seasonally, resembling streaks of damp sand, and contain perchlorate salts that usually get left behind when water evaporates. The observations, made using NASA's Mars Reconnaissance Orbiter (MRO), didn't offer direct evidence of water. But they confirmed scientists' theories about how and where water might form on the planet's surface, and offered hope that these wet patches could contain life — or at least show that something could have survived there once.
