The planet Mars once resembled a young Earth, with a thick atmosphere, flowing surface waters and maybe even life. Today, the planet is a desolate wasteland that has a paper-thin atmosphere and no visible signs of life on its surface. Some scientists are, however, convinced Mars is home to simple, mushroom-like organisms.
According to a controversial paper published in The Journal of Astrobiology and Space Science Research, the surface of Mars is littered with "thousands of mushroom-lichen-like formations".
The supposed Mars mushrooms were photographed by NASA's Curiosity and Opportunity rovers while traversing the Red Planet.
The 15 pictures show clumps of round "puffballs" jutting out from the ground.
The authors have claimed the objects are oriented towards the sky, displaying behaviours typical of mushrooms.