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Deimos, satellite of Mars

 Automatic translation  Automatic translation Updated June 01, 2013

Deimos is the smallest and most distant of the two moons of Mars (the other being Phobos). Deimos is originally a primitive meteorite, because like Phobos, its composition differs from that of Mars.
The moon may have formed in the outer asteroid belt between Mars and Jupiter, because its color and density are close to the C-type asteroids are common in the asteroid belt. It is a small body of irregular shape very dark, turning 30H18mn its orbit at 23,460 km.
It is in synchronous rotation, having, like the Moon or Phobos, always the same face of the planet. Too close to Mars, it may not be visible beyond the 82nd parallel. Deimos appears smoother ground filled with dust regolith, no crater exceeds 3000 m in diameter and the surface appears free of streaks. The layer of regolith could reach 100 m depth and is caused by the spraying of meteorites on the surface.
Given its low gravity: 0.0039 m / s ², due to its small size, a man escape by jumping from the satellite, which is equivalent to an escape velocity of 10m / s.

 Deimos satellite of Mars

Image: Deimos has a smooth surface filled with dust.

Discovered dateAugust,12 1877
Discovered byAsaph Hall
Dimensions7.8 × 6.0 × 5.1 km
Periapsis23 455.5 km
Apoapsis23 470.9 km
Semi-major axis23 463.2 km
Average orbital speed1.3513 km/s
Escape velocity5.556 m/s
Orbital period1.263 d
Inclination to Mars's equator0.93°
Temperature≈233 K
Rotation period Synchronous

Deimos as seen by MRO


Deimos, shown cons, the smaller of the two moons of Mars was photographed Feb. 21, 2009 by the U.S. probe MRO (Mars Reconnaissance Orbiter). The U.S. probe, launched August 12, 2005 from Cape Canaveral base in Florida, helping to enrich our knowledge about Mars, as the history of its water, its climate or its subsoil. It also sent us from time to time, beautiful photos of his satellites Deimos and Phobos. Deimos is oval shaped and not spherical, more like a misshapen asteroid. This small moon of Mars from a few kilometers on a side (15 × 12 × 10.4 km), appears to be completely smooth and very little cratered. This is due to its small size and the layer 100 m thick powdered rock, which covers it. The orbital period of the little moon is 1.26244 days, which means it goes around Mars in one day, 6 hours, 17 minutes and 54 seconds.


Image: Deimos is the smaller of two satellites of Mars.
These two views above cons were taken February 21, 2009, by the camera HiRise (High Resolution Imaging Science Experiment) of the Mars Reconnaissance Orbiter.
Deimos is not spherical, its dimensions are irregular, 15 × 12 × 10.4 km. The photograph shows a light surface cons but in reality, its very dark reddish black surface has an albedo of 0.07. Deimos has a smooth surface because the layer of regolith (fine particles ejected during the impacts of meteorites), which covers its surface with the exception of the more recent impact craters.
This item, with dark reds, like Mars and Phobos, the other moon of Mars.
Image Credit: NASA / JPL-Caltech / University of Arizona. The image resolution is 20 meters per pixel.

 Deimos moon of Mars

Phobos and Deimos


The names of the two moons of Mars are derived from Greek mythology, Phobos (Fear) and Deimos (terror), the twins that the god Ares had with the goddess Aphrodite.
Deimos is covered with a thick layer of particles ejected during the impacts of meteorites, which blurs its relief by filling craters gradually.
There is no such feature on Phobos is closer to Mars, where dust is influenced by tidal forces of Mars.
These two satellites could come from the asteroid belt, which passed near the planet Mars have been captured. Deimos is at a distance of 23,460 km of Mars and Phobos at 9377 km. The gravity at the surface of Deimos is very low (0.0039 m/s-2).
Its density is only 2.2 g/cm3. Its escape velocity is 22 km/hour or 6 m / s), which would allow a man to leave the soil of Deimos simply by running.


Phobos is the larger of the two moons of Mars. It is also the closest, it orbits around the red planet in 7 hours and 39 minutes.
At the time of the shooting, she was 11,800 miles of Mars Express, while Deimos was 26 200 km.

Image: This unique picture of the Martian moons Phobos and Deimos whole, was captured by Mars Express November 5, 2009 by the HRSC instrument (High Resolution Stereo Camera).
Here, Deimos is more than twice as far from the camera than Phobos.

 phobos and deimos

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