Apparent retrograde motion notable on Mars which has two natural satellites, Phobos and Deimos. Both moons orbit Mars in an eastward (prograde) direction, however Deimos has an orbital period of 1.23 Martian sidereal days, making it supersynchronous, whereas Phobos has an orbital period of 0.31 Martian sidereal days making it subsynchronous. Consequently, although both moons are travelling in an eastward (prograde) direction, they appear to be travelling in opposite directions when viewed from the surface of Mars due to their orbital periods in relation to the rotational period of the planet. All other planetary bodies in the Solar System also appear to periodically
Mars One from any money earned from guest appearances (which would amount to a minimal portion of the estimated $6 billion required for the mission). Finally, despite being one of 100 finalists, Roche himself has never spoken to any Mars One employee or representative in person, and instead of psychological or psychometric testing as is normal for astronaut candidates (especially for a lengthy, one-way mission), his interview process consisted of a 10-minute Skype conversation. In April 2015, Mars One's CEO Bas Lansdorp admitted that their 12-year plan for landing humans on Mars by 2027 is mostly fiction. Robert Zubrin, advocate for crewed