A lake of liquid water has been detected beneath the surface of Mars. Here's why it matters that there's water on the red planet.
https://edition.cnn.com/2018/07/25/world/mars-subsurface-water-lake-evidence/index.html?utm_content=2018-07-28T10%3A00%3A07&utm_medium=social&utm_term=video&utm_source=fbCNNi
