August 11, 1877 – The moon of Mars, Deimos and Phobos, are discovered by American astronomer Asaph Hall.

Phobos and Deimos are the two moons of mars. Irregular in shape, (not round) they are named after Phobos (fear and panic) and Deimos (terror and dread), Greek mythological twins. The twins went with their father, Ares, into battle. Ares, the god of war, was known to the Romans as Mars.

https://en.wikipedia.org/wiki/Moons_of_Mars

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