Deimos (pronounced /ˈdaɪməs/ DYE-məs; also /ˈdiːməs/ DEE-məs, as in Greek Δείμος), is the smaller and outer of Mars’ two moons (the other being Phobos). It is named after Deimos, a figure representing dread in Greek Mythology. Its systematic designation is Mars II.
Deimos was discovered by Asaph Hall, Sr. on August 12, 1877 at about 07:48 UTC (given in contemporary sources as "August 11 14:40" Washington mean time using the old astronomical conve...
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Deimos (pronounced /ˈdaɪməs/ DYE-məs; also /ˈdiːməs/ DEE-məs, as in Greek Δείμος), is the smaller and outer of Mars’ two moons (the other being Phobos). It is named after Deimos, a figure representing dread in Greek Mythology. Its systematic designation is Mars II.
Deimos was discovered by Asaph Hall, Sr. on August 12, 1877 at about 07:48 UTC (given in contemporary sources as "August 11 14:40" Washington mean time using the old astronomical convention of beginning a day at noon, so 12 hours must be added to get the actual local mean time). Hall also discovered Phobos at the same time, after deliberately searching for Martian moons.
The names, originally spelled Phobus and Deimus, respectively, were suggested by Henry Madan (1838–1901), Science Master of Eton, from Book XV of the Iliad, where Ares (the Roman god Mars) summons Dread (Deimos) and Fear (Phobos).
Deimos, like Mars' other moon Phobos, has spectra, albedos and densities similar to those of a C or D-type asteroid. Like most...
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