It’s been exactly 687 Earth-days (one Martian year) since Curiosity landed on Mars:
One of Curiosity's first major findings after landing on the Red Planet in August 2012 was an ancient riverbed at its landing site. Nearby, at an area known as Yellowknife Bay, the mission met its main goal of determining whether the Martian Gale Crater ever was habitable for simple life forms. The answer, a historic "yes," came from two mudstone slabs that the rover sampled with its drill. Analysis of these samples revealed the site was once a lakebed with mild water, the essential elemental ingredients for life, and a type of chemical energy source used by some microbes on Earth. If Mars had living organisms, this would have been a good home for them.
Even in an era of such technological prowess, I still can’t believe we’ve managed to place a selfie-taking, remote-controlled robot on the surface of Mars. These are truly interesting times to be alive, as we’re starting to venture beyond the confines of our cozy little blue home.