Deimos

Deimos is the smallest and farthest moon of Mars, the other is Phobos. Deimos rotates about 23,460 km away from Mars and is much smaller than Phobos. The diameter of Deimos is about 12.4 km, and the mass is 1,476,000,000,000,000 kg. Like Phobos, Deimos has an irregular shape and is probably made of stony material with many craters. Deimos moves slowly away from Mars, unlike Phobos. He has a quiet job and will remain stable for the time being. Deimos was discovered in 1877 by Asaph Hall, just like Phobos.