And here are some great images of both Phobos and Deimos

How Many Moons Does Mars Have

moncler sale Many of the planets in our Solar System have a system of moons. But among the rocky planets that make up the inner Solar System, having moons is a privilege enjoyed only by two planets: Earth and Mars. And for these two planets, it is a rather limited privilege compared to gas giants like Jupiter and Saturn which each have dozens of moons. moncler sale

moncler outlet store Whereas Earth has only one satellite (aka. the Moon), Mars has two small moons: Phobos and Deimos. And whereas the vast majority of moons in our Solar System are large enough to become round spheres similar to moncler sale outlet our own Moon, Phobos and Deimos are asteroid sized and misshapen in appearance. phobia). Phobos measures just 22.7 km across and has an orbit that places it closer to Mars than Deimos. Compared to Earth own Moon which orbits at a distance of 384,403 km away from our planet Phobos orbits at an average distance of only 9,377 km above Mars. moncler outlet store

cheap moncler jackets This produces an orbit of short duration https://www.moncler-jacket-outlet.com, revolving around the planet three times in a single day. For someone standing on the planet surface Moncler Outlet, Phobos could be seen crossing the sky in only 4 hours or so. cheap moncler jackets

Mars second moon is Deimos, which takes its name moncler mens jackets from the Greek word for panic. It is even smaller, measuring just 12.6 km across, and is also less irregular in cheap moncler outlet shape. Its orbit places it much farther away from Mars, at a distance of 23,460 km, which means that Deimos takes 30.35 hours to complete an orbit around Mars.

When impacted, dust and debris will leave the surface cheap moncler of the moon because they do not have enough gravitational pull to retain the ejecta. However, the gravity from Mars will keep a ring of this debris around the planet in approximately the same region that the moon orbits. As the moon revolves, the cheap moncler sale debris is redeposited as a dusty layer on its surface.

moncler sale outlet Like Earth Moon, Phobos and Deimos always present the same face to their planet. Both are lumpy, heavily cratered and covered in dust and loose rocks. They are among the darker objects in the solar system. The moons appear to be made of carbon rich rock mixed with ice. Given their composition, size and shape, astronomers think that both of moncler outlet store Mars moons were once asteroids that were captured in the distant past. moncler sale outlet

moncler outlet jackets However, it appears that of these two satellites, Phobos won be orbiting the Red cheap moncler jackets Planet for very much longer. Because it orbits Mars faster than the planet itself rotates, it is slowly spiraling inward. As a result, scientists estimate that in the next 10 50 million years or so, it will get so low that the Martian gravity will tear Phobos into a pile of rocks. And then a few million years later, those rocks will crash down on the surface of Mars in a spectacular string of impacts. moncler outlet jackets

moncler outlet uk Composition and Surface Features: moncler outlet uk

moncler jackets outlet Phobos and Deimos both appear to be composed of C type rock, similar to blackish carbonaceous chondrite asteroids. This family of asteroids is extremely old, dating back to the formation of the Solar System. Hence, it is likely that they were acquired by Mars very early in its history. moncler jackets outlet

moncler jacket sale Phobos is heavily cratered from eons worth of impacts from meteors with three large craters dominating the surface. The largest crater is Stickney (visible in the photo above). The Stickney crater is 10 km in diameter, which is almost half of the average diameter of Phobos itself. The crater is so large that scientists believe the impact came close to breaking the moon apart. Parallel grooves and striations leading away from the crater indicate that fractures were likely formed as a result of the impact. moncler jacket sale

cheap moncler jackets sale Much like Phobos, it surface is pockmarked and cratered from numerous impact. The largest crater on Deimos is approximately 2.3 km in diameter (1/5 the size of the Stickney crater). In addition, their composition (as already noted) is similar to that of C type asteroids that are common to the Asteroid Belt. Hence, the prevailing theory as to their origin is that they were once asteroids that were kicked out of the Main Belt by Jupiter gravity, and were then acquired by Mars. cheap moncler jackets sale

History of Observation:

moncler factory outlet Phobos and Deimos were originally discovered by American astronomer Asaph Hall moncler sale in August of 1877. Ninety four years after the moons discovery, NASA Mariner 9 spacecraft got a much better look at the two moons from its orbit around Mars. Upon viewing the large crater on Phobos, NASA decided to name it after Hall wife Stickney. Subsequent observations conducted by the HiRISE experiment, the Mars moncler outlet online Global Surveyor, and moncler outlet the Mars Reconnaissance Orbiter have added to our overall understanding of these two satellites. moncler factory outlet

Someday, manned missions may be going to Phobos and Deimos. Scientists have discussed the possibility of using one of the Martian moons as a base from which astronauts could observe the Red moncler outlet sale Planet and launch robots to its surface, while shielded by miles of rock from cosmic rays and solar radiation for nearly two thirds of every orbit.

Here an article about how Phobos is going to crash into Mars in the future. And here are some great images of both Phobos and Deimos.

moncler outlet sale Here NASA fact sheet on Mars, including information about the moons, and additional info from Starry Skies. moncler outlet sale

Finally, if you like to learn more about Mars in general, we have done several podcast episodes about the Red Planet at Astronomy Cast. Episode 52: Mars, and Episode 91: The Search for Water on Mars.

moncler outlet online One could mention Mars trojan asteroids, about half a dozen observed. moncler outlet online

cheap moncler outlet I suppose there are many thousands near Mars asteroids, which maybe could be helpful for Mars exploration. Some surely come close to both Earth and Mars and are natural Earth Mars cyclers with resources we could extract without having to launch them from Earth. cheap moncler outlet

cheap moncler coats I think some of the sources used for this article are outdated. More research has been done in recent years, so astronomers are less certain now Their orbits are as if cheap moncler coats they formed together with Mars, but it monlcer down jackets is funny that Phobos only has about 30 million years left if it formed 4500 million years ago. One possibility is that they formed like the Moon, out of debris from a relatively recent impact on Mars. cheap moncler coats

cheap moncler Humans to Mars moons is seriously being considered for the favorable conjunctions in 2031 and 2033. Much easier and cheaper than to land on Mars surface. Should fit politically as a compromise in the endless Mars, Moon and asteroids target choice debate cheap moncler.

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