The 1976 Viking mission to Mars uncovered some tantalizing, and much-debated, evidence of possible previous life on the big, red planet. Now we have the Curiosity rover over there to really sort things out.
Among other adventures, Curiosity is looking for organic molecules. The discovery of organic compounds could indicate previous life on Mars, though that life isn't likely to look like a toothy, long-headed alien that wants to hug your face.
While we wait for the rover to wander around and report back on its findings over the course of its mission, we have plenty of time to speculate about what it might find. … Read more