Scientists spot ancient 'smiley face' on Mars — and it could contain signs of life 

 Newly released images of Mars reveal a "smiley" salt deposit on the Red Planet's surface. A related study suggests that similar deposits, which were left behind from ancient lakes, may be a good place to look for signs of former life on Mars. 

https://cdn.mos.cms.futurecdn.net/vYipSWnSgc6zJsUgKuXPZS.jpg

https://www.space.com/scientists-spot-ancient-smiley-face-on-mars-could-contain-signs-of-life