Rings in 'tree stump' crater found on Mars illuminate red planet's past climate
https://edition.cnn.com/2022/01/31/world/tree-stump-crater-mars-scn/index.html
If it's possible to observe water on Mars, it would be interesting to learn the structure of water. It must be different from that on Earth, because of different soie, different air pressure, and different history.
