Astronomers recently spotted a surprising "smiley face" beaming up from the surface of Mars as they surveyed the alien landscape as part of a new study. The emoticon-like structure, which is only visible under certain conditions, is the remnant of an ancient lake that dried up billions of years ago — and could be harboring signs of former life on the Red Planet.
The European Space Agency (ESA) shared an image of the smiley face in an Instagram post on Sept. 7. The grinning shape, which is made up of a ring of ancient chloride salt deposits with a pair of meteor-crater eyes, was snapped by ESA's ExoMars Trace Gas Orbiter, which has been analyzing the levels of methane and other gases in Mars' wispy atmosphere since 2016.
