Two celestial satellites, commonly called moons, orbit Mars. Their names are Phobos and Deimos. Both satellites are small and irregularly shaped and are most likely fragments of larger objects that were broken apart in collisions.Know More
According to the Smithsonian National Air and Space Museum, Phobos has a radius of 13 miles and is about 3,700 miles away from Mars. Taking a little more than seven hours to orbit Mars, it completely circles the planet more than three times in a Martian day.
Deimos has a radius of only 8 miles and is located 14,580 miles from Mars. This satellite takes about 30 hours to circle the planet.Learn more in Planets
The planet Mars completes its orbit of the sun in just under 687 Earth days. Mars orbits the sun much further away than Earth, and its longer year results from having to travel a greater distance.Full Answer >
Several man-made satellites have been sent to Mars since 1964. The first spacecraft to Mars, known as Mariner 3, was launched on Nov. 5, 1964. This spacecraft malfunctioned and failed to fly by Mars as planned.Full Answer >
Eris, the dwarf planet whose orbit is beyond Neptune's orbit, has one small moon named Dysnomia. The dwarf planet was first spotted in 2003 and confirmed in 2005.Full Answer >
The planet Mercury does not have any known moons (natural satellites) as of 2014. There has been one known artificial satellite orbiting Mercury, known as Messenger.Full Answer >