Extraterrestrial skies Mars appears to be the angular diameter as seen from Earth (0.35°), and sends 40% of the light, approximately the brightness of a slightly cloudy afternoon on Earth. On June 3, 2014, the "Curiosity" rover on Mars observed the planet Mercury transiting the Sun, marking the first time a planetary transit has been observed from a celestial body besides Earth. Mars has two small moons: Phobos and Deimos. From the Martian surface, Phobos has one-third to one-half the angular diameter of the Sun while Deimos is barely more than a dot (only 2′ angular diameter). The orbital period of Phobos
Phobos (audio drama) Phobos (audio drama) Phobos is an audio drama based on the long-running British science fiction television series "Doctor Who". This audio drama was produced by Big Finish Productions and was broadcast on BBC 7 on 28 January 2007. The Doctor and Lucie land on Phobos, the moon of Mars, which has become popular with extreme sports fans in the future, due to a wormhole on the surface which is used for bungee jumping. The Doctor and Lucie listen to Kai Tobias's stories of monsters on the surface, although no-one takes him seriously. Later the monsters from Tobias's stories appear and