Planet Names and Greek Mythology Planet Names How do planets and their moons get ther names? With the exception of Earth, all of the planets in our solar system have names from Greek or Roman mythology. This tradition was continued when Uranus, Neptune, and Pluto were discovered in more modern times. Mercury (Hermes) is the god of commerce, travel and thievery in Roman mythology. The planet probably received this name because it moves so quickly across the sky. Venus (Aphrodite) is the Roman goddess of love and beauty. The planet is aptly named since it makes a beautiful sight in the sky, with only the Sun and the Moon being brighter. Earth (Gaia) is the only planet whose English name does not derive from Greek/Roman mythology. The name derives from Old English and Germanic. There are, of course, many other names for our planet in other languages. Jupiter (Zeus) was the King of the Gods in Roman mythology, making the name a good choice for what is by far the largest planet in our solar system Mars (Ares) is the Roman god of War. The planet probably got this name due to its red color.

Jupiter was the King of the Gods in Roman mythology, making the name a good choice for what is by far the largest planet in our solar system. Saturn (Cronus) is the Roman god of agriculture. Uranus is the ancient Roman deity of the Heavens, the earliest supreme god. Neptune (Poseidon), was the Roman god of the Sea. Given the beautiful blue color of this planet, the name is an excellent choice! Pluto (Hades) is the Roman god of the underworld in Roman mythology. Perhaps the planet received this name because it's so far from the Sun that it is in perpetual darkness. Natural Satellites For those moons have been known for a long time (such as the Galilean moons of Jupiter), the names were assigned from mythological characters. For example, the moons of Jupiter were named for characters who had roles in the life of Zeus (the Greek mythology counterpart of the Roman God Jupiter). For example: Metis (first wife of Zeus) Copyright 2005-16, Greek-Mythology-Gods.com How do planets and their moons get their names? How do planets and their moons get their names?

Answer: The official names of planets and their moons are governed by an organization called the International Astronomical Union (IAU). The IAU was established in 1919. Its mission is "to promote and safeguard the science of astronomy in all its aspects through international cooperation". Its individual members are professional astronomers from all over the World. The IAU is the internationally recognized authority for assigning names to celestial bodies and any surface features on them. The IAU recognizes that astronomy is an old science and many of its names come from long-standing traditions and/or are founded in history. For many of the names of the objects in the solar system , this is especially so. Most of the objects in our solar system received names long ago based on Greek or Roman mythology . The IAU has therefore adopted this tradition in its rules for naming certain types of objects in the solar system. Planets With the exception of Earth, all of the planets in our solar system have names from Greek or Roman mythology. This tradition was continued when Uranus, Neptune, and Pluto were discovered in more modern times. Mercury is the god of commerce, travel and thievery in Roman mythology. The planet probably received this name because it moves so quickly across the sky.

Venus is the Roman goddess of love and beauty. The planet is aptly named since it makes a beautiful sight in the sky, with only the Sun and the Moon being brighter. Earth is the only planet whose English name does not derive from Greek/Roman mythology. The name derives from Old English and Germanic. There are, of course, many other names for our planet in other languages. Mars is the Roman god of War. The planet probably got this name due to its red color. Jupiter was the King of the Gods in Roman mythology, making the name a good choice for what is by far the largest planet in our solar system. Saturn is the Roman god of agriculture. Uranus is the ancient Greek deity of the Heavens, the earliest supreme god. Neptune, was the Roman god of the Sea. Given the beautiful blue color of this planet, the name is an excellent choice! Pluto is the Roman god of the underworld in Roman mythology. Perhaps the planet received this name because it's so far from the Sun that it is in perpetual darkness. Natural Satellites For those moons have been known for a long time (such as the Galilean moons of Jupiter), the names were assigned from mythological characters.

For example, the moons of Jupiter were named for characters who had roles in the life of Zeus (the Greek mythology counterpart of the Roman God Jupiter). For recently discovered natural satellites of the planets, they are first given a "provisional" or temporary name while additional observations are made to confirm their existence. This temporary name (usually consisting of the year of discovery and some number indicating the order of discovery in that year) is assigned by an organization called the Central Bureau for Astronomical Telegrams (CBAT). For example, when Voyager 2 found a bunch of new moons in its 1989 Neptune encounter, they were named S/1989 N 1, S/1989 N 2, etc. When the existence of the object is confirmed (and its orbit determined), it is given a final name. The name is suggested by the discoverer(s), but following tradition is strongly encouraged. Note that the moons of Uranus are a special case in our solar system. They are named after literary characters (from works by William Shakespeare and Alexander Pope) rather then characters from mythology. Surface Features Landscape features on planets and natural satellites follow a set of complicated conventions set by the IAU Nomenclature Committee.

The rules set restrictions on allowable names such as: a planetary feature may not bear the name of a living person or of a political or religious figure from the last 200 years. Solar System Planets: Order of the 8 (or 9) Planets Solar System Planets: Order of the 8 (or 9) Planets By Robert Roy Britt | January 22, 2016 12:35pm ET MORE The planets of the solar system as depicted by a NASA computer illustration. Orbits and sizes are not shown to scale. Credit: NASA Ever since the discovery of Pluto in 1930, kids grew up learning about the nine planets of our solar system. That all changed starting in the late 1990s, when astronomers began to argue about whether Pluto was a planet. In a highly controversial decision , the International Astronomical Union ultimately decided in 2006 to call Pluto a “dwarf planet,” reducing the list of “real planets” in our solar system to eight. However, astronomers are now hunting for another planet in our solar system, a true ninth planet , after evidence of its existence was unveiled on Jan.

20, 2016. The so-called "Planet Nine," as scientists are calling it, is about 10 times the mass of Earth and 5,000 times the mass of Pluto. [ Solar System Pictures: A Photo Tour ] If you insist on including Pluto , then that world would come after Neptune on the list; Pluto is truly way out there, and on a wildly tilted, elliptical orbit (two of the several reasons it got demoted). Interestingly, Pluto used to be the eighth planet, actually. More on that below. Terrestrial planets The inner four worlds are called “ terrestrial planets ,” because, like Earth, their surfaces are all rocky. Pluto, too, has a solid surface (and a very frozen one) but has never been grouped with the four terrestrials. Jovian planets The four large outer worlds — Jupiter, Saturn, Uranus, and Neptune — are known as the “Jovian planets” (meaning “Jupiter-like”) because they are all huge compared to the terrestrial planets, and because they are gaseous in nature rather than having rocky surfaces (though some or all of them may have solid cores, astronomers say).

According to NASA , "two of the outer planets beyond the orbit of Mars — Jupiter and Saturn — are known as gas giants; the more distant Uranus and Neptune are called ice giants." This is because, while the first two are dominated by gas, while the last two have more ice. All four contain mostly hydrogen and helium. Dwarf planets The IAU definition of a full-fledged planet goes like this: A body that circles the sun without being some other object's satellite, is large enough to be rounded by its own gravity (but not so big that it begins to undergo nuclear fusion, like a star) and has "cleared its neighborhood" of most other orbiting bodies. Yeah, that’s a mouthful. The problem for Pluto, besides its small size and offbeat orbit, is that it shares its space with lots of other objects in the Kuiper Belt , beyond Neptune. Still, the demotion of Pluto remains controversial . The IAU planet definition puts other small, round worlds in the dwarf planet category, including the Kuiper Belt objects Eris , Haumea , and Makemake . Also now a dwarf planet is Ceres , a round object in the Asteroid Belt between Mars and Jupiter.

Ceres was actually considered a planet when discovered in 1801 and then later deemed to be an asteroid. Some astronomers like to consider Ceres as a 10th planet (not to be confused with Nibiru or Planet X ), but that line of thinking opens up the possibility of there being 13 planets, with more bound to be discovered. The planets Below is a brief overview of the eight primary planets in our solar system , in order from the inner solar system outward: Mercury The closest planet to the sun, Mercury is only a bit larger than Earth's moon. Its day side is scorched by the sun and can reach 840 degrees Fahrenheit (450 Celsius), but on the night side, temperatures drop to hundreds of degrees below freezing. Mercury has virtually no atmosphere to absorb meteor impacts, so its surface is pockmarked with craters, just like the moon. Over its four-year mission, NASA's MESSENGER spacecraft has revealed views of the planet that have challenged astronomers' expectations.

Discovery: Known to the ancients and visible to the naked eye Named for: Messenger of the Roman gods Diameter: 3,031 miles (4,878 km) Orbit: 88 Earth days Venus' southern hemisphere, as seen in the ultraviolet. Credit: ESA Venus The second planet from the sun, Venus is terribly hot, even hotter than Mercury. The atmosphere is toxic. The pressure at the surface would crush and kill you. Scientists describe Venus’ situation as a runaway greenhouse effect. Its size and structure are similar to Earth, Venus' thick, toxic atmosphere traps heat in a runaway "greenhouse effect." Oddly, Venus spins slowly in the opposite direction of most planets. The Greeks believed Venus was two different objects — one in the morning sky and another in the evening. Because it is often brighter than any other object in the sky — except for the sun and moon — Venus has generated many UFO reports.

Discovery: Known to the ancients and visible to the naked eye Named for: Roman goddess of love and beauty Diameter: 7,521 miles (12,104 km) Orbit: 225 Earth days An image of the Earth taken by the Russian weather satellite Elektro-L No.1. Credit: NTsOMZ Earth The third planet from the sun, Earth is a waterworld, with two-thirds of the planet covered by ocean. It’s the only world known to harbor life. Earth’s atmosphere is rich in life-sustaining nitrogen and oxygen. Earth's surface rotates about its axis at 1,532 feet per second (467 meters per second) — slightly more than 1,000 mph (1,600 kph) — at the equator. The planet zips around the sun at more than 18 miles per second (29 km per second).

Diameter: 7,926 miles (12,760 km) Orbit: 365.24 days Day: 23 hours, 56 minutes Related: Mars researchers are focusing both Earth-based and planet orbiting sensors to better understand sources of methane on the red planet. Image Credit: Space Telescope Science Institute Mars The fourth planet from the sun, is a cold, dusty place. The dust, an iron oxide, gives the planet its reddish cast. Mars shares similarities with Earth: It is rocky, has mountains and valleys, and storm systems ranging from localized tornado-like dust devils to planet-engulfing dust storms. It snows on Mars. And Mars harbors water ice. Scientists think it was once wet and warm, though today it’s cold and desert-like. Mars' atmosphere is too thin for liquid water to exist on the surface for any length of time. Scientists think ancient Mars would have had the conditions to support life, and there is hope that signs of past life — possibly even present biology — may exist on the Red Planet.

Discovery: Known to the ancients and visible to the naked eye Named for: Roman god of war Diameter: 4,217 miles (6,787 km) Orbit: 687 Earth days Day: Just more than one Earth day (24 hours, 37 minutes) Related: Close-up of Jupiter's Great Red Spot as seen by a Voyager spacecraft. Credit: NASA/JPL-Caltech Jupiter The fifth planet from the sun, Jupiter is huge and is the most massive planet in our solar system. It’s a mostly gaseous world, mostly hydrogen and helium. Its swirling clouds are colorful due to different types of trace gases. A big feature is the Great Red Spot, a giant storm which has raged for hundreds of years. Jupiter has a strong magnetic field, and with dozens of moons, it looks a bit like a miniature solar system.

Discovery: Known to the ancients and visible to the naked eye Named for: Ruler of the Roman gods Diameter: 86,881 miles (139,822 km) Orbit: 11.9 Earth years The shadow of Saturn's moon Mimas dips onto the planet's rings and straddles the Cassini Division in this natural color image taken as Saturn approaches its August 2009 equinox. Credit: NASA/JPL/Space Science Institute Saturn The sixth planet from the sun is known most for its rings . When Galileo Galilei first studied Saturn in the early 1600s, he thought it was an object with three parts. Not knowing he was seeing a planet with rings, the stumped astronomer entered a small drawing — a symbol with one large circle and two smaller ones — in his notebook, as a noun in a sentence describing his discovery. More than 40 years later, Christiaan Huygens proposed that they were rings. The rings are made of ice and rock. Scientists are not yet sure how they formed. The gaseous planet is mostly hydrogen and helium. It has numerous moons .

Discovery: Known to the ancients and visible to the naked eye Named for: Roman god of agriculture Diameter: 74,900 miles (120,500 km) Orbit: 29.5 Earth years Day: About 10.5 Earth hours Related: Near-infrared views of Uranus reveal its otherwise faint ring system, highlighting the extent to which the planet is tilted. Credit: Lawrence Sromovsky, (Univ. Wisconsin-Madison), Keck Observatory Uranus The seventh planet from the sun, Uranus is an oddball. It’s the only giant planet whose equator is nearly at right angles to its orbit — it basically orbits on its side. Astronomers think the planet collided with some other planet-size object long ago, causing the tilt. The tilt causes extreme seasons that last 20-plus years, and the sun beats down on one pole or the other for 84 Earth-years. Uranus is about the same size as Neptune. Methane in the atmosphere gives Uranus its blue-green tint. It has numerous moons and faint rings.

Discovery: 1781 by William Herschel (was thought previously to be a star) Named for: Personification of heaven in ancient myth Diameter: 31,763 miles (51,120 km) Orbit: 84 Earth years Neptune’s winds travel at more than 1,500 mph, and are the fastest planetary winds in the solar system. Credit: NASA/JPL Neptune The eighth planet from the sun, Neptune is known for strong winds — sometimes faster than the speed of sound. Neptune is far out and cold. The planet is more than 30 times as far from the sun as Earth. It has a rocky core. Neptune was the first planet to be predicted to exist by using math, before it was detected. Irregularities in the orbit of Uranus led French astronomer Alexis Bouvard to suggest some other might be exerting a gravitational tug. German astronomer Johann Galle used calculations to help find Neptune in a telescope. Neptune is about 17 times as massive as Earth. Discovery: 1846 Pluto and its moons orbit the sun near the edge of our solar system.

Learn all about Pluto's weirdly eccentric orbit, four moons and more in this Space.com infographic . Credit: SPACE.com/Karl Tate Pluto (Dwarf Planet) Once the ninth planet from the sun, Pluto is unlike other planets in many respects. It is smaller than Earth's moon. Its orbit carries it inside the orbit of Neptune and then way out beyond that orbit. From 1979 until early 1999, Pluto had actually been the eighth planet from the sun. Then, on Feb. 11, 1999, it crossed Neptune's path and once again became the solar system's most distant planet — until it was demoted to dwarf planet status. Pluto will stay beyond Neptune for 228 years. Pluto’s orbit is tilted to the main plane of the solar system — where the other planets orbit — by 17.1 degrees. It’s a cold, rocky world with only a very ephemeral atmosphere. NASA's New Horizons mission performed history's first flyby of the Pluto system on July 14, 2015.

[Related: New Horizons' Pluto Flyby: Latest News, Images and Video ] Discovery: 1930 by Clyde Tombaugh Named for: Roman god of the underworld, Hades Diameter: 1,430 miles (2,301 km) Orbit: 248 Earth years NASA Solar System Exploration: Dwarf Planets Planet Nine Planet Nine orbits the sun at a distance that is 20 times farther out than the orbit of Neptune. (The orbit of Neptune is 2.7 billion miles from the sun at its closest point.) The strange world's orbit is about 600 times farther from the sun than the Earth's orbit is from the star. Scientists have not actually seen Planet Nine directly . Its existence was inferred by its gravitational effects on other objects in the Kuiper Belt, a region at the fringe of the solar system that is home to icy objects left over from the birth of the sun and planets. Saturn | Define Saturn at Dictionary.com Saturn noun 1. an ancient Roman god of agriculture, the consort of Ops, believed to have ruled the earth during an age of happiness and virtue, identified with the Greek god Cronus. 2. Astronomy.

the planet sixth in order from the sun, having an equatorial diameter of 74,600 miles (120,000 km), a mean distance from the sun of 886.7 million miles (1427 million km), a period of revolution of 29.46 years, and 21 known moons. It is the second largest planet in the solar system, encompassed by a series of thin, flat rings composed of small particles of ice. 3. Alchemy. the metal lead. 4. a U.S. space-vehicle booster developing from 2 million to 9 million pounds (900,000 to 4 million kg) of thrust for launching satellites, probes, and spaceships. Dictionary.com Unabridged Examples from the Web for Saturn Expand Contemporary Examples Saturn direct Monday in your cosmic zone of “others” causes sudden shifts in status between you and significants. Andiron Tales John Kendrick Bangs Saturn produces death by privation and obstructions, by chills and colds. Andiron Tales John Kendrick Bangs We don't know when this mutiny is to come off, but we are close to Saturn now; it can't be long.

British Dictionary definitions for Saturn Expand the Roman god of agriculture and vegetation Greek counterpart Cronus Saturn2 noun 1. one of the giant planets, the sixth planet from the sun, around which revolve planar concentric rings (Saturn's rings) consisting of small frozen particles. The planet has 62 satellites. Mean distance from sun: 1425 million km; period of revolution around sun: 29.41 years; period of axial rotation: 10.23 hours; equatorial diameter and mass: 9.26 and 95.3 times that of the earth, respectively See also Titan 2 2. a large US rocket used for launching various objects, such as a spaceprobe or an Apollo spacecraft, into space 3. the alchemical name for lead 2 Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd.

1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012 Word Origin and History for Saturn Expand Old English Sætern, a Roman god, also "most remote planet" (then known), from Latin Saturnus, originally a name of an Italic god of agriculture, possibly from Etruscan. Derivation from Latin serere (past participle satus) "to sow" is said to be folk-etymology. An ancient Italic deity, popularly believed to have appeared in Italy in the reign of Janus, and to have instructed the people in agriculture, gardening, etc., thus elevating them from barbarism to social order and civilization. His reign was sung by the poets as "the golden age." [Century Dictionary] Identified with Greek Kronos, father of Zeus. Also the alchemical name for lead (late 14c.).

In Akkadian, the planet was kaiamanu, literally "constant, enduring," hence Hebrew kiyyun, Arabic and Persian kaiwan "Saturn." Related: Saturnian. Online Etymology Dictionary, © 2010 Douglas Harper Saturn (sāt'ərn) The sixth planet from the Sun and the second largest, with a diameter about ten times that of Earth. Saturn is a gas giant that is almost as large as Jupiter in diameter but with only about 30 percent of Jupiter's mass. Its mainly gaseous composition together with its rapid axial rotation (it rotates once every 10.5 hours) cause a noticeable flattening at the poles and a prominent equatorial bulge. Saturn is encircled by a large, flat system of rings made up of rock fragments and tiny ice crystals, first observed by Galileo in 1610. The rings are believed to be unstable and therefore likely of recent origin; they may have been formed from bodies such as asteroids or moons that were shattered as they approached closer than the Roche limit.

Saturn has numerous moons, of which the largest is Titan, the second largest moon in the solar system after Jupiter's Ganymede and larger than both Mercury and Pluto. See Table at solar system . The American Heritage® Science Dictionary Copyright © 2002. Published by Houghton Mifflin. All rights reserved. Expand Saturn definition The Roman name for one of the Titans , the father of Zeus . In Roman mythology , Saturn fled from Mount Olympus after Zeus defeated the Titans. He settled in Italy and established a golden age, in which all people were equal and harvests were plentiful. Note: Saturday (“Saturn's day”) is named after Saturn. Note: The sixth planet from the sun (the Earth is third) is named Saturn. Saturn definition In astronomy , the second-largest major planet , sixth from the sun. Saturn was named for the Roman god of agriculture. Like Jupiter , Saturn is composed largely of gas es and liquids . Saturn is the most distant planet plainly visible to the naked eye. (See solar system ; see under “Mythology and Folklore.”) Note: Saturn, often called the most beautiful planet, is known for the rings that encircle it.

The American Heritage® New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved. Planetary Names: Planet and Satellite Names and Discoverers International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN) Planetary Names: Planet and Satellite Names and Discoverers Home Named Mercurius by the Romans because it appears to move so swiftly. Discoverer 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. Other civilizations have named it for their god or goddess of love/war. Discoverer Earth The name Earth comes from the Indo-European base 'er,'which produced the Germanic noun 'ertho,' and ultimately German 'erde,' Dutch 'aarde,' Scandinavian 'jord,' and English 'earth.' Related forms include Greek 'eraze,' meaning 'on the ground,' and Welsh 'erw,' meaning 'a piece of land.' Earth I (Moon) Every civilization has had a name for the satellite of Earth that is known, in English, as the Moon.

The Moon is known as Luna in Italian, Latin, and Spanish, as Lune in French, as Mond in German, and as Selene in Greek. Martian System The names of the moons of Mars and the English translations of the names were specifically proposed by their discoverer, Asaph Hall, and as such, they have been accepted and retained under the current IAU nomenclature. Body Discoverer 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." Mars I (Phobos) Inner satellite of Mars. Named for one of the horses that drew Mars' chariot; also called an "attendant" or "son" of Mars, according to chapter 15, line 119 of Homer's "Iliad." This Greek word means "flight." August 17, 1877 A.

Hall Mars II (Deimos) This outer Martian satellite was named for one of the horses that drew Mars' chariot; also called an "attendant" or "son" of Mars, according to chapter 15, line 119 of Homer's "Iliad." Deimos means "fear" in Greek. August 11, 1877 Selected Asteroids (of the Main Belt) and their Satellites Body Named for the Greek god of love. August 13, 1898 Named for a resort on the Crimean Peninsula. July 30, 1916 G. Neujmin (243) Ida Named for a nymph who raised the infant Zeus. Ida is also the name of a mountain on the island of Crete, the location of the cave where Zeus was reared. September 29, 1884 J. Palisa (243) Ida I (Dactyl) Named for a group of mythological beings who lived on Mount Ida, where the infant Zeus was hidden and raised (according to some accounts) by the nymph Ida.

August 28, 1993 Galileo imaging and infrared science teams. (253) Mathilde The name was suggested by a staff member of the Paris Observatory who first computed an orbit for Mathilde. The name is thought to honor the wife of the vice director of the Paris Observatory at that time. November 12, 1885 J. Palisa (22) Kalliope I (Linus) Satellite of (22) Kalliope. In various accounts of Greek mythology, Linus is considered to be the son of the Muse Kalliope and the inventor of melody and rhythm. August 29 and September 2, 2001 Mauna Kea J.-L. Margot, M.E. Brown, W.J. Merline, F. Menard, L. Close, C. Dumas, C.R. Chapman, and D.C. Slater (45) Eugenia I (Petit-Prince) Satellite of (45) Eugenia.

The Little Prince, Napolean-Eugene-Louis-Jean-Joseph Bonaparte (1856-1879), was the son of Eugenia de Montijo de Guzm\'an and Napoleon III. November 1, 1998 Mauna Kea W.J. Merline, L. Close, C. Dumas, C.R. Chapman, F. Roddier, F. Menard, D.C. Slater, G. Duvert, C. Shelton, and T. Morgan Jovian System Satellites in the Jovian system are named for Zeus/Jupiter's lovers and descendants. Names of outer satellites with a prograde orbit generally end with the letter "a" (although an "o" ending has been reserved for some unusual cases), and names of satellites with a retrograde orbit end with an "e." Body Discoverer 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 I (Io) Io, the daughter of Inachus, was changed by Jupiter into a cow to protect her from Hera's jealous wrath.

But Hera recognized Io and sent a gadfly to torment her. Io, maddened by the fly, wandered throughout the Mediterranean region. January 8, 1610 Padua Galileo (Simon Marius probably made an independent discovery of the Galilean satellites at about the same time that Galileo did, and he may have unwittingly sighted them up to a month earlier, but the priority must go to Galileo because he published his discovery first.) Jupiter II (Europa) Beautiful daughter of Agenor, king of Tyre, she was seduced by Jupiter, who had assumed the shape of a white bull. When Europa climbed on his back he swam with her to Crete, where she bore several children, including Minos. January 8, 1610 Galileo (who evidently observed the combined image of Io and Europa the previous night) Jupiter III (Ganymede) Beautiful young boy who was carried to Olympus by Jupiter disguised as an eagle. Ganymede then became the cupbearer of the Olympian gods.

January 7, 1610 Galileo Jupiter IV (Callisto) Beautiful daughter of Lycaon, she was seduced by Jupiter, who changed her into a bear to protect her from Hera's jealousy. January 7, 1610 Galileo Jupiter V (Amalthea) A naiad who nursed the new-born Jupiter. She had as a favorite animal a goat which is said by some authors to have nourished Jupiter. The name was suggested by Flammarion. September 9, 1892 A Rhodian nymph who bore three sons of Zeus. December 4, 1904 C.D. Perrine Jupiter VII (Elara) Daughter of King Orchomenus, a paramour of Zeus, and by him the mother of the giant Tityus. January 3, 1905 C.D. Perrine Jupiter VIII (Pasiphae) Wife of Minos, king of Crete. Zeus made approaches to her as a bull (taurus). She then gave birth to the Minotaur.

(Spelling changed from Pasiphaë to Pasiphae July 2009.) January 27, 1908 P.J. Melotte Jupiter IX (Sinope) Daughter of the river god Asopus. Zeus desired to make love to her. Instead of this he granted perpetual virginity, after he had been deceived by his own promises. (In the same way, she also fooled Apollo.) July 21, 1914 S.B. Nicholson Jupiter X (Lysithea) Daughter of Kadmos, also named Semele, mother of Dionysos by Zeus. According to others, she was the daughter of Evenus and mother of Helenus by Jupiter. July 6, 1938 Daughter of the river god Achelous and stepdaughter of Zeus. October 19, 1999 J.V. Scotti, T.B. Spahr, R.S. McMillan, J.A. Larson, J. Montani, A.E. Gleason, and T. Gehrels Jupiter XVIII (Themisto) Daughter of the Arcadian river god Inachus, mother of Ister by Zeus.

September 30, 1975, rediscovered November 21, 2000 Palomar, rediscovered at Mauna Kea C.T. Kowal and E. Roemer (1975), and S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, G. Magnier, M. Holman, B.G. Marsden, and G.V. Williams (2000). Jupiter XIX (Megaclite) Daughter of Macareus, who with Zeus gave birth to Thebe and Locrus. November 25, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XX (Taygete) Daughter of Atlas, one of the Pleiades, mother of Lakedaimon by Zeus. November 25, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXI (Chaldene) Bore the son Solymos with Zeus.

November 26, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXII (Harpalyke) Daughter and wife of Clymenus. In revenge for this incestuous relationship, she killed the son she bore him, cooked the corpse, and served it to Clymenus. She was transformed into the night bird called Chalkis, and Clymenus hanged himself. Some say that she was transformed into that bird because she had intercourse with Zeus. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXIII (Kalyke) Nymph who bore the handsome son Endymion with Zeus. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXIV (Iocaste) Wife of Laius, King of Thebes, and mother of Oedipus. After Laius was killed, Iocaste unknowingly married her own son Oedipus.

When she learned that her husband was her son, she killed herself. Some say she was the mother of Agamedes by Zeus. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXV (Erinome) Daughter of Celes, compelled by Venus to fall in love with Jupiter. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXVI (Isonoe) A Danaid, bore with Zeus the son Orchomenos. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXVII (Praxidike) Goddess of punishment, mother of Klesios by Zeus. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXVIII (Autonoe) Mother of the Graces by Zeus according to some authors.

December 10, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXIX (Thyone) Semele, mother of Dionysos by Zeus. She received the name of Thyone in Hades by Dionysos before he ascended up with her from there to heaven. December 11, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXX (Hermippe) Consort of Zeus and mother of Orchomenos by him. December 9, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXI (Aitne) A Sicilian nymph, conquest of Zeus. December 9, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXII (Eurydome) Mother of the Graces by Zeus, according to some authors. (Source: Cornutus: Theologiae Graecae compendium 15) December 9, 2001 S.S. Sheppard, D.C.

Jewitt and J. Kleyna Jupiter XXXIII (Euanthe) The mother of the Graces by Zeus, according to some authors. December 11, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXIV (Euporie) One of the Horae, a daughter of Zeus and Themis. December 11, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXV (Orthosie) One of the Horae, a daughter of Zeus and Themis. December 11, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXVI (Sponde) One of the Horae (Seasons), daughter of Zeus. December 9, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXVII (Kale) One of the Graces, a daughter of Zeus, husband of Hephaistos. December 9, 2001 S.S. Sheppard, D.C. Jewitt and J.

Kleyna Jupiter XXXVIII (Pasithee) One of the Graces, a daughter of Zeus. December 11, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXIX (Hegemone) One of the Graces, a daughter of Zeus. February 8, 2003 Discoverer Saturn Roman name for the Greek Cronos, father of Zeus/Jupiter. Other civilizations have given different names to Saturn, which is the farthest planet from Earth that can be observed by the naked human eye. Most of its satellites were named for Titans who, according to Greek mythology, were brothers and sisters of Saturn. Saturn I (Mimas) Named by Herschel's son John in the early 19th century for a Giant felled by Hephaestus (or Ares) in the war between the Titans and Olympian gods. July 18, 1789 W. Herschel Saturn II (Enceladus) Named by Herschel's son John for the Giant Enceladus. Enceladus was crushed by Athene in the battle between the Olympian gods and the Titans.

Earth piled on top of him became the island of Sicily. August 28, 1789 W. Herschel Saturn III (Tethys) Cassini wished to name Tethys and the other three satellites that he discovered (Dione, Rhea, and Iapetus) for Louis XIV. However, the names used today for these satellites were applied in the early 19th century by John Herschel, who named them for Titans and Titanesses, brothers and sisters of Saturn. Tethys was the wife of Oceanus and mother of all rivers and Oceanids. March 21, 1684 Named by Pickering for one of the Titanesses. August 16, 1898 W.H. Pickering Saturn X (Janus) First reported (though with an incorrect orbital period) and named by A. Dollfus from observations in Dec. 1966, this satellite was finally confirmed in 1980. It was proven to have a twin, Epimetheus, sharing the same orbit but never actually meeting. It is named for the Roman god of the beginning. The two-faced god could look forward and backward at the same time.

December 15, 1966 (Dollfus), February 19, 1980 (Pascu) Pic du Midi (Dollfus), Washington (Pascu) A. Dollfus (1966), D. Pascu (1980) Saturn XI (Epimetheus) First suspected by J. Fountain and S. Larson as confusing the detection of Janus. They assigned the correct orbital period, and the satellite was finally confirmed in 1980. Named for the son of the Titan Iapetus. In contrast with his far-sighted brother Prometheus, he "subsequently realized" that he was in the wrong. 1977 (Fountain and Larson), February 26, 1980 (Cruikshank) Tucson (Fountain and Larson), Mauna Kea (Cruikshank) J. Fountain and S. Larson (1977), D. Cruikshank (1980) Saturn XII (Helene) A granddaughter of Kronos, for her beauty she triggered off the Trojan War.

March 1, 1980 P. Laques and J. Lecacheux Saturn XIII (Telesto) Daughter of the Titans Oceanus and Tethys. April 8, 1980 B.A. Smith, H. Reitsema, S.M. Larson, and J. Fountain Saturn XIV (Calypso) Daughter of the Titans Oceanus and Tethys and paramour of Odysseus. March 13, 1980 D. Pascu, P.K. Seidelmann, W. Baum, and D. Currie Saturn XV (Atlas) A Titan; he held the heavens on his shoulders. October 1980 Voyager Science Team Saturn XVI (Prometheus) Son of the Titan Iapetus, brother of Atlas and Epimetheus, he gave many gifts to humanity, including fire. October 1980 Voyager Science Team Saturn XVII (Pandora) Made of clay by Hephaestus at the request of Zeus. She married Epimetheus and opened the box that loosed a host of plagues upon humanity.

October 1980 Voyager Science Team Saturn XVIII (Pan) Greek god of pastoralism, he was half goat and half human. Son of Hermes, brother of Daphnis, and a descendant of the Titans. Discovered orbiting in the Encke division in Saturn's A ring. 1990 Ymir is the primordial Norse giant and the progenitor of the race of frost giants. August 7, 2000 La Silla B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XX (Paaliaq) Named for an Inuit giant. August 7, 2000 La Silla B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXI (Tarvos) Named for a Gallic giant. September 23, 2000 Mauna Kea B. Gladman, J.

Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXII (Ijiraq) Named for an Inuit giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXIII (Suttungr) Named for a Norse giant who kindled flames that destroyed the world. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXIV (Kiviuq) Named for an Inuit giant. August 7, 2000 La Silla B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M.

Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXV (Mundilfari) Named for an Norse giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXVI (Albiorix) Named for a Gallic giant who was considered to be the king of the world. November 9, 2000 Named for a Norse giantess. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXVIII (Erriapus) Named for a Gallic giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H.

Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXIX (Siarnaq) Named for an Inuit giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXX (Thrymr) Named for a Norse giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXXI (Narvi) Named for a Norse giant. February 5, 2003 S.S. Sheppard, D.C. Jewitt, and J. Kleyna Saturn XXXII (Methone) One of the Alkyonides, the seven beautiful daughters of the Giant Alkyoneos. June 1, 2004 S.

Sheppard, D.C. Jewitt, J. Kleyna Saturn XXXVIII (Bergelmir) Norse frost giant, son of Ymir and one of the Hrimthursar, one of only two members of the frost giant race to escape being drowned in Ymir's blood. December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XXXIX (Bestla) Norse primeval goddess, mother of deities, daughter of the giant Bolthorn. December 13, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XL (Farbauti) Norse storm giant, father of Loki. December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XLI (Fenrir) Norse monstrous wolf, son of Loki and the giantess Angurboda, father of Hati and Skoll. December 13, 2004 S. Sheppard, D.C. Jewitt, J.

Kleyna Saturn XLII (Fornjot) Early Norse storm giant, father of Aegir, Kari, and Loge. December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XLIII (Hati) Gigantic Norse wolf, twin of Skoll. December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XLIV (Hyrrokkin) Norse giantess who launched Balder's funeral ship. (Spelling changed from Hyrokkin.) December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XLV (Kari) Named for the grotesque, brutish slave in Shakespeare's "The Tempest." September 6, 1997 B. Gladman, P. Nicholson, J.A. Burns and J. Kavelaars Uranus XVII (Sycorax) Named for Caliban's mother in Shakespeare's "The Tempest." September 6, 1997 P. Nicholson, B.

Gladman, J. Burns and J. Kavelaars Uranus XVIII (Prospero) Named for the rightful Duke of Milan in "The Tempest." July 18, 1999 M. Holman, J. Kavelaars, B. Gladman, J.-M. Petit, and H. Scholl Uranus XIX (Setebos) Setebos was a new-world (South American) deity's name that Shakespeare popularized as Sycorax's god in "The Tempest." July 18, 1999 J. Kavelaars, B. Gladman, M. Holman, J.-M. Petit, and H. Scholl Uranus XX (Stephano) Named for a drunken butler in "The Tempest." July 18, 1999 B. Gladman, M. Holman, J. Kavelaars, J.-M. Petit, and H. Scholl Uranus XXI (Trinculo) A jester in Shakespeare's "The Tempest." August 13, 2001 M. Holman, J.J.

Kavelaars and D. Milisavljevic Uranus XXII (Francisco) A lord in "The Tempest." August 13, 2001 J. Kavelaars, M. Holman, D. Milisavljevic, and T. Grav Uranus XXIII (Margaret) A gentlewoman attending on Hero from "Much Ado About Nothing." August 29, 2003 Discoverer Neptune Neptune was "predicted" by John Couch Adams and Urbain Le Verrier who, independently, were able to account for the irregularities in the motion of Uranus by correctly predicting the orbital elements of a trans- Uranian body. Using the predicted parameters of Le Verrier (Adams never published his predictions), Johann Galle observed the planet in 1846. Galle wanted to name the planet for Le Verrier, but that was not acceptable to the international astronomical community. Instead, this planet is named for the Roman god of the sea. September 23, 1846 J.G. Galle Neptune I (Triton) Triton is named for the sea-god son of Poseidon (Neptune) and Amphitrite.

The first suggestion of the name Triton has been attributed to the French astronomer Camille Flammarion. October 10, 1846 W. Lassell Neptune II (Nereid) The Nereids were the fifty daughters of the sea god Nereus and Doris and were attendants of Poseidon (Neptune). May 1, 1949 G.P. Kuiper Neptune III (Naiad) The name of a group of Greek water nymphs who were guardians of lakes, fountains, springs, and rivers. August 1989 One of the Nereids, the fifty daughters of Nereus and Doris. August 14, 2002 M. Holman, J. Kavelaars, T. Grav, W. Fraser, and D. Milisavljevic Neptune X (Psamathe) One of the Nereids, lover of Aeacus and mother of Phocus. August 29, 2003 S.S. Sheppard, D.C. Jewitt, and J.

Kleyna Neptune XI (Sao) One of the Nereids, the fifty daughters of Nereus and Doris. August 14, 2002 T. Grav, M. Holman, J. Kavelaars, W. Fraser, and D. Milisavljevic Neptune XII (Laomedeia) One of the Nereids, the fifty daughters of Nereus and Doris. August 13, 2002 J. Kavelaars, M. Holman, T. Grav, W. Fraser, and D. Milisavljevic Neptune XIII (Neso) One of the Nereids, the fifty daughters of Nereus and Doris. August 14, 2002 Discoverer (134340) Pluto Pluto was discovered at Lowell Observatory in Flagstaff, AZ during a systematic search for a trans-Neptune planet predicted by Percival Lowell and William H. Pickering. Named after the Roman god of the underworld who was able to render himself invisible. January 23, 1930 C.W.

Tombaugh (134340) Pluto I (Charon) Named after the Greek mythological boatman who ferried souls across the river Styx to Pluto for judgement. April 13, 1978 J.W. Christy (134340) Pluto II (Nix) Goddess of darkness and night, mother of Charon. (Nix is the Egyptian spelling of the Greek name Nyx.) May 15, 2005 Hubble Space Telescope H.A. Weaver, S.A. Stern, M.J. Mutchler, A.J. Steffl, M.W. Buie, W.J. Merline, J.R. Spencer, E.F. Young, and L.A. Young (134340) Pluto III (Hydra) In Greek mythology, terrifying monster with the body of a serpent and nine heads that guarded the underworld. May 15, 2005 Hubble Space Telescope H.A. Weaver, S.A. Stern, M.J. Mutchler, A.J. Steffl, M.W. Buie, W.J. Merline, J.R. Spencer, E.F.

Young, and L.A. Young (134340) Pluto IV (Kerberos) In Greek mythology, the many-headed dog that guarded the entrance to the underworld. June 28, 2011 M.R. Showalter, D.P. Hamilton, S.A. Stern, H.A. Weaver, A.J. Steffl, and L.A. Young (134340) Pluto V (Styx) Mercury In Roman mythology Mercury is the god of commerce, travel and thievery, the Roman counterpart of the Greek god Hermes, the messenger of the Gods. The planet probably received this name because it moves so quickly across the sky. Mercury has been known since at least the time of the Sumerians (3rd millennium BC). The IAU changed the definition of "planet" so that Pluto no longer qualifies. There are officially only eight planets in our solar system. Of course this change in terminology does not affect what's actually out there. In the end, it's not very important how we classify the various objects in our solar system. What is important is to learn about their physical nature and their histories.

Planet Order from the Sun; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune Our knowledge of our solar system is extensive but it is far from complete. Some of the worlds have never even been photographed up close. The Nine Planets is an overview of what we know today. We are still exploring, much more is still to come: We shall not cease from exploration, and the end of all our exploring will be to arrive where we started and know the place for the first time. -- T. S. Eliot Space Today Online -- Exploring the Solar System Planet Pluto Pluto was the most recent major planet to be discovered. It was found in 1930 during a sky survey by American amateur astronomer Clyde Tombaugh at Lowell Observatory in Arizona. Tombaugh died in 1997. Hubble sees Pluto and its moon Charon (NASA) Pluto was the name for Hades in ancient Greek myth. Hades was god of the netherworld — the home of the dead. Similarly, to the ancient Romans, Pluto was god of the underworld. The planet may have been given the name Pluto because it is so far from the Sun that it is in perpetual darkness.

Another factor may have been Percival Lowell's initials PL. Lowell had founded the Lowell Observatory in Arizona in 1894. Pluto has been a favorite with people on our inner Solar System planet ever since discovery of the faraway body was one of the biggest news stories of 1930. After the planet discovery became popular, Walt Disney named Mickey Mouse's dog in its honor. Moon. Pluto has a natural satellite, Charon , which is larger in proportion to its planet than any moon of any planet in the Solar System. The moon Charon, which was discovered in 1978 by Jim Christy, may be a chunk that broke off Pluto in a collision between the planet and some other large object. Before Charon was found to be a separate body, blurred-together images of Pluto and Charon led astronomers to believe Pluto was a much larger single body. Today, some astronomers think of Pluto and Charon as a double planet rather than planet and moon. The word Charon is pronounced "KAIR en." Alternatively, some pronounce it "SHAHR en." The moon is named for the ferryman who conveyed the dead across the River Styx or the River Acheron to Hades.

In Greek mythology, Styx was the river across which the souls of the dead were ferried, one of the five rivers of Hades. Another of the five was Acheron, the river of woe. A long way off. Pluto's average distance from the Sun is 3.67 billion miles. That's 39.5 times the average distance between the Sun and Earth. The small planet is estimated to be 1,440 miles in diameter. That's only 70 percent as big as Earth's Moon. In fact, Pluto is smaller than seven of the Solar System's moons — Io, Europa, Ganymede, Callisto, Titan, Triton and Earth's Moon. Prior to the discovery of Charon, Earth's Moon held the distinction of being the largest moon relative to the size of its planet. Other planets. How does Pluto differ from the eight major planets? Body. Pluto is is a small, cold, dark, frozen, rugged, uneven, craggy place. By comparison, the nearest planets to Pluto in the outer Solar System are giant gas-bags. Pluto seems to be composed mostly of rock and ice with a thin atmosphere of nitrogen, carbon monoxide and methane.

Pluto's mass is only 0.2 percent of planet Earth's mass. Orbit. Pluto has a strange orbit. It was the only one to cross another planet's orbit. Pluto's orbit tilts up from the Solar System plane. It takes Pluto 6 days 9 hours to rotate and 248 Earth years to complete an orbit around the Sun. It's orbit is off-center in relation to the Sun. That leads Pluto across planet Neptune's path. Size. Pluto is less than half the size of any major planet. It's only about two-thirds the size of Earth's Moon. Pluto's diameter is 1,430 miles. That's a mere18 percent of planet Earth's diameter. Moon. Pluto's natural satellite, Charon, is larger in proportion to its planet than any planet's moon. Pluto At a Glance Day: 6 Earth days 9 hours Year: 248 Earth years Satellite: Charon Crossing Neptune. From 1979 to 1999, Pluto was the eighth planet from the Sun. In 1999, it crossed Neptune's path to again become the Solar System's most distant planet.

It will remain in the ninth position for 228 years before crossing inside Neptune's orbit again. Pluto and Netpune will never collide because their orbits are very different. Pluto can be visualized as above Neptune in the orbital plane. The two bodies always are separated by more than a billion miles. Pluto's origin. The dwarf planet's origin is unknown. Some astronomers suggest Pluto may have been a moon of Neptune that escaped. Others say Pluto might be a comet or asteroid which wandered in amongst the planets from a region just outside the Solar System known as the Kuiper Belt, which is said to contain comets that orbit the Sun in a plane similar to the major planets. Most of the little we know about Pluto has been learned since the late 1970s. Many of the key questions about Pluto and its natural satellite Charon await the close-up observation of an unmanned robot-probe spaceflight mission from Earth. New Horizons >> Pluto was the only one of the nine planets that had not been visited by a probe from Earth. A one-way trip from Earth to Pluto would take an interplanetary probe a dozen years. New Horizons will arrive at Pluto in 2015.

Pluto was reclassified into a new category of dwarf planets on August 24, 2006, by some 2,500 astronomers from 75 nations, meeting as the International Astronomical Union. They demoted the small planet leaving only eight major planets in the Solar System – Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The IAU definition covers planets and other Solar System bodies, except satellites: Planet is a celestial body that: is in orbit around the Sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and has cleared the neighborhood around its orbit. Dwarf planet is a celestial body that is in orbit around the Sun, has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, has not cleared the neighbourhood around its orbit, and is not a satellite. Small Solar System Bodies are all other objects, except satellites, orbiting the Sun. The category includes most of the Solar System asteroids, most Trans-Neptunian Objects, comets, and other small bodies.

Pluto was defined as a dwarf planet and recognized as the prototype of a new category of Trans-Neptunian Objects. Pluto circles the Sun in an oblong orbit overlapping the orbit of Neptune's. Learn more about Pluto...

Question: What is the only major planet of the Solar System that takes its English name from Greek mythology?
Answer: Uranus