Published on 2026-10-07
A moon that rises in the west
Phobos is the largest of the two moons of Mars and is distinguished by a very particular orbital speed. It orbits the planet in only 7 h 39 min, while a Martian day lasts 24 h 37 min. This speed, which is higher than that of the rotation of Mars, causes a curious phenomenon where Phobos rises in the west and sets in the east.
Astronomie sur MarsPhobos et Déimos
Written by AI from Wikipedia — CC BY-SA 4.0