User:Wonghk3/Sandbox/WikiText Case Study Planet Mars

Guide to Planet Mars ancestry, family history, and genealogy birth records, marriage records, death records, census records, family history, and military records.

Introduction
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury. In English, Mars carries a name of the Roman god of war and is often referred to as the 'Red Planet'. The latter refers to the effect of the iron oxide prevalent on Mars' surface, which gives it a reddish appearance distinctive among the astronomical bodies visible to the naked eye. Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the valleys, deserts, and polar ice caps of Earth.

Location
The following are the most historically relevant planets in the Solar System.

Natural Satellites
Mars has two relatively small (compared to Earth's) natural moons, Phobos (about 22 km (14 mi) in diameter) and Deimos (about 12 km (7.5 mi) in diameter), which orbit close to the planet. Asteroid capture is a long-favored theory, but their origin remains uncertain.