Mars has two moons which orbits around it, the smaller of these two is Deimos. Though being the smallest moon that orbits Mars it was the first of the moons to be discovered. With a diameter of 12km Deimos is about half the size of its big brother Phobos as well as among the smallest moons in our Solar System.
Deimos is rather irregular in its shape, which is due the small size, though yet it would appear as a very bright star if viewed from Mars. The surface of Deimos is made from a very dark rock which is called carbonaceous chondrite, this rock element contains a lot of carbon. The little moon also has water ice on its surface. Deimos are quite alike the Earth’s Moon, as it is filled with craters from decades of meteors which have hit the surface, neither does it have an atmosphere.
The gravity on Deimos is extremely small compared to the gravity force on Earth; this is to do the relatively small size of Deimos. The gravity force is so low that it would be very dangerous to walk on this moon’s surface without a type of restraint which would keep the people safe from pushing themselves by accident away from Deimos.
Many astrology scientists are extremely interested in Deimos and exploring this moon. The reason for this is that it is believed that Deimos originally was an asteroid which was captured by Mars a long time ago. The scientist’s hopes that they through studies of Deimos will get a better idea and closer view of other similar sized asteroids in our Solar System may look like.
Deimos is was is known as tidally locked to Mars, this means that it will at all times keep the same side facing Mars during its complete orbit around the planet. This is because that 1 Deimos day lasts for 30.5 hours, but it also takes 30.5 hours to orbit Mars. If people would stand on Deimos, on the side turned towards Mars, they will notice that the planet takes up close to one eleventh of the visible sky, thus making Mars a large object to look at. At the planet Mars this creates an interesting situation, because of Mars own rotation period. If a person would look on the sky of Mars, they would be able to see moon rise east and the moon set in the west horizon.