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Deimos Facts

Deimos Facts
Deimos is the smaller of Mars' two moons, the other being Phobos. It was discovered by American astronomer Asaph Hall, Sr. at the United States Naval Observatory in Washington D.C. on August 12, 1877. These two asteroid-size moons are two of the smallest moons in the Solar System. They appear to be composed of material similar to Type I or II carbonaceous chondrites which is the material that makes up asteroids and dwarf planets. Deimos is seven times larger than Phobos. It orbits much farther from Mars than its brother moon at 14,580 miles (23,460 kilometers) from Mars. Unlike Phobos, which rises in the west and sets in the east, Deimos rises in the east and sets in the west. Deimos orbits around Mars in 30.3 hours.
Interesting Deimos Facts:
Hall named this moon after the Greek god of War, Deimos, a son of Ares (Mars) and Aphrodite (Venus), and the brother of Phobos. The name Deimos means dread or terror.
Scientists are unsure of the birth of Phobos and Deimos. Some scientists concluded that they came from the asteroid belt, with Jupiter's gravity long ago nudging them into orbit around Mars. Others believed these dark moons may have formed as satellites around Mars, created by dust and rock that was drawn together by gravity. Another hypothesis is that Mars may have had an existing moon that may have collided with the red planet and created dust and rubble which drew together to form Phobos and Deimos.
Deimos is a very small, lumpy, heavily cratered object, though smoother than Phobos. It has a radius of 3.9 miles (6.2 kilometers) and takes 30.3 hours to orbit Mars. When Deimos eclipses the sun, it appears as a tiny dot moving across its surface. During full moon, Deimos shines as bright as the planet Venus which is one of the brightest objects in our Solar System.
Unlike the moon Phobos that will collide with Mars in 50-100 million years, the orbit of Deimos is moving the moon away from Mars. At some point, the moon will move off into space when it gets too far from Mars' gravity to remain in orbit.
Deimos has a very odd, irregular shape and is not spherical like other moons in the Solar System.
The average temperature of Deimos is minus 40.15 degrees Celsius.
There are only two geological features on Deimos that have been named. They are the two largest craters on the moon. The crater named Swift has a diameter of 1,000 miles and was named after Jonathan Swift who was the author of Gulliver's Travels who wrote about the two moons of Mars 151 years before they were discovered.
The second crater is Voltaire which has a diameter of 1900 miles and was named after the French writer Francois-Marie Arouet who was known by the pen name Voltaire.
Deimos has been photographed by many different spacecraft whose primary mission was to photograph the planet Mars. The first craft to orbit the planet was the Mariner 9 in 1971, however no landings have ever taken place on this moon.


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