How the Planets and Satellites Got Their Names MERCURY Named for the winged Roman god of travel because it appears to move so swiftly. VENUS Roman name for the goddess of love. This planet was considered to be the brightest and most beautiful planet or star in the heavens. EARTH The name Earth comes from the Indo-European base 'er,' which produced the Germanic noun 'ertho,' and ultimately German 'erde,' Dutch 'aarde,' Danish and Swedish 'jord,' and English 'earth.' Related forms include Greek 'eraze,' meaning 'on the ground,' and Welsh 'erw,' meaning 'field.' SATELLITES: THE MOON - Every civilization has had a name for the satellite of Earth that is known, in English, as the Moon. The name is of Anglo-Saxon derivation. MARS Named by the Romans for their god of war because of its red, bloodlike color. Other civilizations also named this planet from this attribute; for example, the Egyptians named it “Her Desher,” meaning “the red one.” SATELLITES: Phobos (named for one of the horses that drew Mars' chariot); Deimos (named for one of Mars' companions). JUPITER The largest and most massive of the planets was named Zeus by the Greeks and Jupiter by the Romans; he was the most important deity in both pantheons. Jupiter's satellites are named after mythological characters who have some relationship to Zeus. SATELLITES: Metis (first wife of Zeus); Adrastea (a nymph of Crete to whose care Zeus's mother entrusted the infant Zeus); Amalthea (a goat in some accounts, a princess of Crete in others, she suckled Zeus as a young child); Thebe (a nymph abducted by Zeus); Io (she was changed by Zeus into a cow to protect her from his jealous wife); Europa (she was seduced by Jupiter); Ganymede (beautiful young boy who became the cupbearer of the Olympian gods); Callisto (she was seduced by Zeus, who changed her into a bear to protect her from his wife's jealousy); Leda (seduced by Zeus in the form of a swan); Himalia (nymph who bore three sons of Zeus); Lysithia (one of Zeus' many lovers); Elara (a paramour of Zeus); Ananke (daughter of Zeus and Adrastea, goddess of fate and necessity); Carme (mother, by Zeus, of Britomartis); Pasiphaë (wife of Minos, mother of the Minotaur); Sinope (daughter of the river god Asopus and Merope). Other recently discovered and named satellites of Jupiter are: Themisto, Euporie, Orthosie, Euanthe, Thyone, Harpalyke, Hermippe, Praxidike, Iocaste, Passithee, Chaldene, Kale, Isonoe, Aitne, Erinome, Taygete, Kalyke, Eurydome, Autonoe, Sponde, Megaclite, and Callirrhoe. There are still 24 more Jovian satellites to be named. SATURN Saturn was the Roman name for the Greek Cronos, god of farming and the father of Zeus/Jupiter. Some of its satellites were named for Titans who, according to Greek mythology, were brothers and sisters of Saturn. The newest satellites were named for Gallic (Gaul, or ancient France), Norse, and Inuit (Eskimo) giants. SATELLITES: Pan (the half-human, half-goat god of pastoralism); Atlas (a Titan who held the heavens on his shoulders); Prometheus (a Titan who gave many gifts to humanity, including fire); Pandora (a woman who opened the box that loosed a host of plagues upon humanity); Janus (a two-faced Roman god who could look forward and backward at the same time); Epimetheus (a Greek backward-looking god); Mimas (a Titan felled by Hephaestus); Enceladus (a Titan killed by Athene); Tethys (the wife of Oceanus and mother of all rivers); Telesto (a water nymph); Calypso (a daughter of Atlas and paramour of Odysseus); Dione (a sister of Cronos); Helene (a daughter of Zeus); Rhea (a daughter of Cronos); Titan; Hyperion (a Titan); Iapetus (a Titan); Phoebe (another name for Artemis, goddess of the moon). Satellites discovered in 2000 are: Kiviuq, Ijiraq, Paaliaq, Skadi, Albiorix, Erriapo, Siarnaq, Tarvos, Mundilfari, Suttung, Thrym, and Ymir. One more satellite, discovered in 2003, is yet to be named. URANUS Uranus was named for the Greek god of the sky. The astronmer William Lassell, who discovered two of Uranus' satellites in 1851, started the tradition of naming all of the planet's satellites for characters in the work of William Shakepseare and Alexander Pope. SATELLITES: Cordelia (daughter of Lear in Shakespeare's “King Lear”); Ophelia (daughter of Polonius, fiance of Hamlet in Shakespeare's “Hamlet”); Bianca (daughter of Baptista, sister of Kate in Shakespeare's “Taming of the Shrew”); Cressida (title character in Shakespeare's “Troilus and Cressida”); Desdemona (wife of Othello in Shakespeare's “Othello”); Juliet (heroine of Shakespeare's “Romeo and Juliet”); Portia (rich heiress in Shakespeare's “Merchant of Venice”); Rosalind (daughter of the banished duke in Shakespeare's “As You Like It”); Belinda (character in Pope's “Rape of the Lock”); Puck (mischievous spirit in Shakespeare's “A Midsummer Night's Dream”); Miranda (the heroine of Shakespeare's “The Tempest”); Ariel (a benevolent spirit in Shakespeare's “The Tempest”); Umbriel (a malevolent spirit in Pope's“ Rape of the Lock”); Titania (the queen of the fairies in Shakespeare's “A Midsummer Night's Dream”); Oberon (the king of the fairies in “A Midsummer Night's Dream”); Caliban (the brutish slave in Shakespeare's “The Tempest”); Sycorax (Caliban's mother in “The Tempest”); Prospero (the rightful Duke of Milan in “The Tempest”); Setebos (a false god worshiped by Caliban in “The Tempest”); Stephano (a drunken butler in “The Tempest”); Trinculo (a jester in “The Tempest”). NEPTUNE Neptune, a blue planet, was named for the Roman god of the sea. SATELLITES: Naiad (a group of Greek water nymphs who were guardians of lakes, fountains, springs and rivers); Thalassa (Greek sea goddess); Despina (daughter of Neptune); Galatea (one of the attendants of Neptune); Larissa (a lover of Neptune); Proteus (a Greek sea god); Triton (the sea-god son of Poseidon/Neptune); Nereid (the Nereids, a group of fifty daughters, were attendants of Neptune). Five other recently discovered satellites are still unnamed. PLUTO News Flash — Pluto Demoted! Once known as the smallest, coldest, and most distant planet from the Sun, Pluto has a dual identity, not to mention being enshrouded in controversy since its discovery in 1930. On August 24, 2006, the International Astronomical Union (IAU) formally downgraded Pluto from an official planet to a dwarf planet. According to the new rules a planet meets three criteria: it must orbit the Sun, it must be big enough for gravity to squash it into a round ball, and it must have cleared other things out of the way in its orbital neighborhood. The latter measure knocks out Pluto and 2003UB313 (Eris), which orbit among the icy wrecks of the Kuiper Belt, and Ceres, which is in the asteroid belt. Pluto, the “dwarf planet” in our solar system, was named after Roman god of the underworld, who was able to render himself invisible. SATELLITE: Charon (the mythological boatman who ferried souls across the river Styx to Pluto for judgement). Source: The U.S. Geological Survey