The findings are part of a second big batch of papers, being published today in the journal Science, to come from Curiosity. In the first batch, scientists characterized some of the soils Curiosity encountered and determined there's some water in Martian dirt that future human visitors might be able to extract. In this set of discoveries, scientists learned more about the history of water, rocks and radiation in the Gale Crater. They also determined where to look for organic compounds, molecules that are necessary for most life forms and are made by life forms. Scientists have not yet found abundant organics on Mars, but think it's still possible to unearth (unmars?) them, if they look in the right places. The trouble is that the Martian surface is exposed to radiation that breaks down organic compounds, even if they ever did once exist on the planet.