The larger and innermost of the planet Mars' two moons. Phobos was discovered by Asaph Hall on August 17, 1877. In Greek mythology, Phobos was the son of Ares (Mars) and Aphrodite (Venus) and was the ...
Mars is the fourth planet from the Sun. Mars' diameter is 6,790 km and takes 687 days to orbit the Sun. Mars is named after the Roman god of war. In Eastern Asian cultures Mars is also known as the ...
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