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
Timeline of Mars Science Laboratory to the drill mechanism and the rover started moving again on December 9. The robotic arm is functional, and the "Curiosity" team performed diagnostics on the drill mechanism throughout 2017. On June 4, 2018, NASA announced that "Curiosity" ability to drill has been sufficiently restored by changing the drilling methods. Since September 15, 2018, a glitch in "Curiosity"'s active computer (Side-B) has prevented "Curiosity" from storing science and key engineering data. On October 3, 2018, the JPL began operating "Curiosity" on its backup computer (Side-A). "Curiosity" will store science and engineering data normally using its Side-A computer until the cause