Moons

Out of every moon in the solar system, Phobos is the closest to its respective planet. It was nearly shattered by a giant impact and hit thousands of times by meteorites. It will collide with Mars 50 million years from now. Every 100 years Phobos gets 6 feet closer to Mars. It's surface is layered with a fine dust that is unable to retain heat and may be the cause of the intense change in temperature it experiences from day to night. It drops from 25 to -170 degrees farenheit. (NASA)

Deimos is one of the smallest moons in the solar system with a radius of only 3.9 miles. Much like Phobos, it is lumpy from lots of pummeling from meteorites. Every impact lots of debris is shot up and then lands back on the surface, resulting in a thick regolith of 328 feet deep. Regolith is dust on the surface of moons, but each particle is sharp with the lack of atmosphere and erosion. Breathing in regolith would destroy human lungs with thousands of tiny cuts. (NASA)