Phobos

noun
Pho·bos | \ˈfō-ˌbōs, -bəs, ˈfä-\

Definition of Phobos 

astronomy

: the larger and innermost of the two satellites of Mars with an irregular shape and a diameter of approximately 15.6 miles (26.6 km) Phobos is covered with a dusty regolith caused by continual meteoric battering. Because of the moonlet's low gravity, almost all the ejecta from these impacts flies off the surface altogether, but it goes into the same orbit around Mars that Phobos is in, and thus falls back onto Phobos in a constant rain. Phobos orbits Mars within a giant torus of this debris, like the "Peanuts" character Pigpen, who walks around inside a cloud of his own dirt. — Henry S. F. Cooper, Jr., New Yorker, 11 June 1990

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First Known Use of Phobos

1878, in the meaning defined above

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Dictionary Entries near Phobos

-phobic

phobic

phobism

Phobos

phobotactic

phobotaxis

phoby cat

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The first known use of Phobos was in 1878

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