Moons of Mars Sun's angular diameter as seen from Mars, by contrast, is about 21'. Thus there are no total solar eclipses on Mars, as the moons are far too small to completely cover the Sun. On the other hand, total lunar eclipses of Phobos are very common, happening almost every night. The motions of Phobos and Deimos would appear very different from that of our own Moon. Speedy Phobos rises in the west, sets in the east, and rises again in just eleven hours, while Deimos, being only just outside synchronous orbit, rises as expected in the east but very slowly. Despite
Phobos (moon) who studied Phobos and people and places from Jonathan Swift's "Gulliver's Travels". A number of craters have been named, and are listed in the following table. There is one named regio, "Laputa Regio", and one named planitia, "Lagado Planitia"; both are named after places in "Gulliver's Travels" (the fictional Laputa, a flying island, and Lagado, imaginary capital of the fictional nation Balnibarbi). The only named ridge on Phobos is "Kepler Dorsum", named after the astronomer Johannes Kepler. The orbital motion of Phobos has been intensively studied, making it "the best studied natural satellite in the Solar System" in terms of