Timeline of Mars Science Laboratory microorganisms, as well as ancient water, including fluvio-lacustrine environments (plains related to ancient rivers or lakes) that may have been habitable. The search for evidence of habitability, taphonomy (related to fossils), and organic carbon on the planet Mars is now a primary NASA objective. On September 11, 2014 (Sol 746), "Curiosity" reached the slopes of Aeolis Mons (or Mount Sharp), the rover mission's long-term prime destination and where the rover is expected to learn more about the history of Mars. "Curiosity" had traveled an estimated linear distance of to the mountain slopes since leaving its ""start"" point in Yellowknife Bay
Curiosity (rover) ("Mount Sharp"), at the center of the wide crater. Thus, it is believed that the rover may have the opportunity to study two billion years of Martian history in the sediments exposed in the mountain. Additionally, its landing site is near an alluvial fan, which is hypothesized to be the result of a flow of ground water, either before the deposition of the eroded sediments or else in relatively recent geologic history. According to NASA, an estimated 20,000 to 40,000 heat-resistant bacterial spores were on "Curiosity" at launch, and as much as 1,000 times that number may not have been