5 June 2014
Deimos is the smaller and outermore of the two natural satellites of the planet Mars with a mean radius of 6.2 km, the other being Phobos. Deimos takes 30.3 hours to orbit Mars. Its systematic designation is Mars II. The name “Deimos” is pronounced /ˈdaɪməs/ dy-məs, or sometimes /ˈdiːməs/ dee-məs or like the Greek Δείμος. In Greek mythology, Deimos was the twin brother of Phobos and personified Terror.