All Things Space, UFOs, etc.Mars was half covered by an ocean Posted on January 21, 2026 by Administrator Using images from cameras on Mars orbiters, an international research team led by the University of Bern has discovered structures on Mars that are very similar to classic river deltas on Earth. These are traces of rivers that have deposited their sediments into an ocean. This shows that Mars was a “blue planet” around three billion years ago.