<P> SpaceX uses multiple redundant flight computers in a fault - tolerant design in the Falcon 9 rocket . Each Merlin engine is controlled by three voting computers, with two physical processors per computer that constantly check each other's operation . Linux is not inherently fault - tolerant (no operating system is, as it is a function of the whole system including the hardware), but the flight computer software makes it so for its purpose . For flexibility, commercial off - the - shelf parts and system - wide "radiation - tolerant" design are used instead of radiation hardened parts . As of June 2015, SpaceX has made 19 launches of the Falcon 9 since 2010, out of which 18 have successfully delivered their primary payloads to Earth orbit, including some support missions for the International Space Station . </P> <P> In addition, Windows was used as an operating system on non-mission critical systems‍--‌laptops used on board the space station, for example‍--‌but it has been replaced with Linux; the first Linux - powered humanoid robot is also undergoing in - flight testing . </P> <P> The Jet Propulsion Laboratory has used Linux for a number of years "to help with projects relating to the construction of unmanned space flight and deep space exploration"; NASA uses Linux in robotics in the Mars rover, and Ubuntu Linux to "save data from satellites". </P> <P> Linux distributions have been created to provide hands - on experience with coding and source code to students, on devices such as the Raspberry Pi . In addition to producing a practical device, the intention is to show students "how things work under the hood". </P>

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