一块极地夹心蛋糕
The Martian ice cap is like a cake with every layer telling a story. In this case, the story is one of climate change on Mars. This image of an exposed section of the north polar layered deposits (NPLD) looks much like a delicious slice of layered tiramisu. The NPLD is made up of water-ice and dust particles stacked one on top of the other. However, instead ...