mccannbrandonJkM1siZE — 2021-03-17 22:09:36 UTC Galileo originally called Jupiter's moons the Medicean planets, after the Medici family and referred to the individual moons numerically as I, II, III, and IV. The largest body in the asteroid belt, Ceres has amassed a number of references in science fiction stories of the 20th and 21st centuries. All of the stars in the Milky Way orbit a supermassive black hole at the galaxy's center, which is estimated to be some 4 million times as massive as our sun. It has three different diameters (making it a tri-axial ellipsoid): 67 x 51 x 45 miles (108 x 82 x 72 kilometers). Further observations found hydrogen in other areas as well. Near the surface, Earth has an atmosphere that consists of 78 percent nitrogen, 21 percent oxygen, and 1 percent other gases such as argon, carbon dioxide and neon. The photographs taken during this close flyby of a comet nucleus show jets of dust and a rugged, textured surface. The names Io, Europa, Ganymede, and Callisto were officially adopted after it became apparent that naming moons by number would be very confusing as new additional moons were being discovered. ISON was destroyed when it passed too close the the sun. Pluto's rotation is retrograde: it rotates backwards, from east to west (Uranus and Venus also have retrograde rotations). They charted the seasons, created calendars and monitored solar and lunar eclipses. As Earth orbits the sun, it completes one rotation every 23.9 hours. Jupiter's environment is probably not conducive to life as we know it. Our sun is one of at least 100 billion stars in the Milky Way, a spiral galaxy about 100,000 light years across. This gives Jupiter the largest ocean in the solar system — an ocean made of hydrogen instead of water.