Water on Mars of these salts". NASA also reported that Jake M rock, a rock encountered by "Curiosity" on the way to Glenelg, was a mugearite and very similar to terrestrial mugearite rocks. On December 9, 2013, NASA reported that Mars once had a large freshwater lake inside Gale Crater, that could have been a hospitable environment for microbial life. On December 16, 2014, NASA reported detecting an unusual increase, then decrease, in the amounts of methane in the atmosphere of the planet Mars; in addition, organic chemicals were detected in powder drilled from a rock by the "Curiosity" rover. Also, based on
Mars sample-return mission complexity and technical problems. One mission concept (provisionally named simply Mars Sample-Return) was originally considered by NASA's Mars Exploration Program to return samples by 2008, but was cancelled following a review of the program. A NASA-ESA concept mission was aborted in 2012. The United States' Mars Exploration Program, formed after "Mars Observer" failure in September 1992, supported a Mars sample-return. One example of a mission architecture was the "Groundbreaking Mars Sample-Return" by MacPhereson in the early 2000s. In early 2011, the National Research Council's Planetary Science Decadal Survey, which laid out mission planning priorities for the period 2013–2022 at the