Phobos is the larger of Mars’s two moons. It is a small, irregularly shaped object that orbits the Red Planet at a relatively low altitude. Phobos is named after the Greek god of fear, and it is often described as a potato-shaped moon.

Physical Characteristics

• Size: Phobos is about 17 miles (27 kilometers) long, 11 miles (18 kilometers) wide, and 9 miles (15 kilometers) thick. It is one of the smallest moons in the solar system.
• Surface: Phobos is covered in craters, some of which are quite large. The largest crater on Phobos is Stickney Crater, which is about 5 miles (8 kilometers) wide.
• Atmosphere: Phobos does not have a significant atmosphere. Any atmosphere it once had would have been lost to space due to its small size and low gravity.

Orbit

Phobos orbits Mars at an average distance of about 9,377 miles (15,093 kilometers). It has a relatively short orbital period of just 7 hours and 39 minutes. Due to its low orbit, Phobos is slowly spiraling inward toward Mars. Scientists estimate that it will eventually collide with the planet or break apart within the next few million years.

Exploration of Phobos

Phobos has been visited by several spacecraft, including the Mariner 9, Viking 1, and Viking 2 missions. The most recent spacecraft to visit Phobos was the Mars Express orbiter, which took detailed images of the moon in 2004.

Future Missions

There are plans for future missions to Phobos. One such mission is the Phobos-Grunt mission, which was launched by Russia in 2011 but failed to reach Mars. If successful, this mission would have collected samples from Phobos and returned them to Earth for study.

Phobos is a fascinating object that offers scientists a unique opportunity to study the history of the solar system. As we continue to explore this mysterious moon, we may learn more about the formation of Mars and the possibility of life on other planets.