Robust Research - Mars
rme
Here is syndicated link to an article describing the proof that oxygen and life bearing conditions were once present on Mars.
Extract:
"It is difficult for manganese oxide to form on the surface of Mars, so we didn’t expect to find it in such high concentrations in a shoreline deposit,” said Patrick Gasda, of Los Alamos National Laboratory’s Space Science and Applications group and lead author on the study. “On Earth, these types of deposits happen all the time because of the high oxygen in our atmosphere produced by photosynthetic life, and from microbes that help catalyze those manganese oxidation reactions."