In those drill sites, Curiosity detected deposits containing an iron carbonate material called siderite. According to Ben Tutolo, a University of Calgary associate professor of Earth, Energy, and Environment Studies as well as a NASA Mars Science Laboratory Curiosity Rover team, the data marks a major moment in the search for extraterrestrial life.

There, embedded in the bedrock, the Curiosity rover has identified a mineral called siderite that can only have formed from the precipitation of carbon from the Martian atmosphere. In other words, billions of years ago,