乐生活This chocolate chiffon cake, er, I mean this stone, reveals a very complicated history of formation. The stories related to water or wind can be seen just by stacking dozens of layers. More interestingly, the cake, er, the stone, is not on the earth. It’s a Mars rock that Curiosity has been on Mars for more than seven years and is currently observing carefully. So what was Mars like then? Source: NASA/JPL-Caltech/MSSS
