Mars collapse. In 2012, it was proposed that Valles Marineris is not just a graben, but a plate boundary where of transverse motion has occurred, making Mars a planet with possibly a two-tectonic plate arrangement. Images from the Thermal Emission Imaging System (THEMIS) aboard NASA's Mars Odyssey orbiter have revealed seven possible cave entrances on the flanks of the volcano Arsia Mons. The caves, named after loved ones of their discoverers, are collectively known as the "seven sisters". Cave entrances measure from wide and they are estimated to be at least deep. Because light does not reach the floor of most
Mars hoax about twice as far away for the same apparent size. It has nine times the mass of the Moon, and would have about the same tidal effect (nine times the larger mass divided by relative distance cubed). The hoax has resurfaced a number of times since 2003, often showing an altered image of twin moons over the Nilov Monastery, and may continue to do so, always announcing an imminent close Earth–Mars approach. The content of the original email, although almost entirely correct for August 27, 2003, has falsely been redated to announce a new close Earth–Mars approach—the real close approach