Neighbors on Mars

The samples examined by Curiosity above are from different parts of Mars, the left “Wopmay” from Endurance Crater and the right “sheepbay” from Gale Crater.

Perhaps the thought of a human once living on Mars could be an idea that is too far-fetched, but could nothing have ever thrived in our neighboring planet? The Curiosity rover sent to Mars has clearly proven that, at one point in time, we might have had extraterrestrial neighbors, although these may have only been microbes. Curiosity collected a rock sample in Gale Crater and scientists were able to identify some of the key chemical ingredients for life: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. Moreover, Curiosity has also been able to discover the end of ancient river system in the Yellowknife Bay area it was exploring and, in Gale Crater, fine-grained mud-stone proves multiple periods of wet conditions, nodules and veins. Now we have more reason to believe we might have never been alone in the universe, the challenge that lies ahead for Curiosity is to prove that we still aren't alone.