Comparative planetary science closest analogue is the Pluto-Charon system, though its axial tilt is completely different. Both our Moon and Charon are hypothesized to have formed via giant impacts. Giant impacts are hypothesized to account for both the tilt of Uranus, and the retrograde rotation of Venus. Giant impacts are also candidates for the Mars ocean hypothesis, and the high density of Mercury. Most giant planets (except Neptune) have retinues of moons, rings, ring shepherds, and moon Trojans analogous to mini-solar systems. These systems are postulated to have accreted from analogous gas clouds, and possibly with analogous migrations during their formation periods. The
Alien Legacy of the system. The Beta Caeli system is similar to our real-life solar system, with a barren, rocky inner planet, terrestrial planets in the habitable zone of the inner system, followed by gas giants in the outer system that first increase and then decrease in size, and a tiny rock outermost. The naming of the Caelian planets closely matches that of naming planets in our solar system. But while our system uses the names of Roman deities (except for Uranus), Caeli has Greek ones; Gaea is the Greek goddess of the Earth, and Rhea is her daughter. In addition, as