Timeline of Mars Science Laboratory Sun, marking the first time a planetary transit has been observed from a celestial body besides Earth. On June 24, 2014, "Curiosity" completed a Martian year—687 Earth days—after finding that Mars once had environmental conditions favorable for microbial life. On June 27, 2014, "Curiosity" crossed the of its "" and is now in territory that may get even more interesting, especially in terms of Martian geology and landscape (). On July 12, 2014, "Curiosity" imaged the first laser spark on Mars (; video (01:07).) On August 6, 2014, "Curiosity" celebrated its second anniversary since landing on Mars in 2012. On
Mars Exploration Rover one Martian year anniversary (669 sols or 687 Earth days) on November 20, 2005. "Opportunity" celebrated its anniversary on December 12, 2005. At the beginning of the mission, it was expected that the rovers would not survive much longer than 90 Martian days. The Columbia Hills were "just a dream", according to rover driver Chris Leger. "Spirit" explored the semicircular rock formation known as Home Plate. It is a layered rock outcrop that puzzles and excites scientists. It is thought that its rocks are explosive volcanic deposits, though other possibilities exist, including impact deposits or sediment borne by wind or