155 relations: Abbott Lawrence Lowell, Alan Stern, Albedo, Alexis Bouvard, Apparent magnitude, Apparent retrograde motion, Apsis, Arequipa, Argument of periapsis, Armin Otto Leuschner, Asteroid, Astronomical unit, Astronomy & Astrophysics, Atacama Large Millimeter Array, Backyard Worlds, Blink comparator, Brahma, Brian G. Marsden, Camille Flammarion, Cartesian coordinate system, Cassini–Huygens, Chad Trujillo, Charon (moon), Christian Heinrich Friedrich Peters, Classical mechanics, Clearing the neighbourhood, Clyde Tombaugh, CNN, Comet, Comet Swift–Tuttle, Complutense University of Madrid, David C. Jewitt, David Peck Todd, Detached object, Dwarf planet, E. Myles Standish, Earth, Ecliptic, Ernest William Brown, Europa (moon), Fictional planets of the Solar System, Flagstaff, Arizona, Galactic tide, Galilean moons, Ganymede (moon), Gas giant, George Biddell Airy, George Forbes (scientist), Gerard Kuiper, Giant planet, ..., Gná and Hófvarpnir, Gotha, Gotha Observatory, Halley's Comet, Hamilton College (New York), Hans E. Lau, Harlow Shapley, Harvard College Observatory, Heinrich Louis d'Arrest, IAU definition of planet, Icarus (journal), Infrared cirrus, International Astronomical Union, Io (moon), IRAS, Jacques Babinet, James Ferguson (American astronomer), James W. Christy, Jet Propulsion Laboratory, Jet Propulsion Laboratory Development Ephemeris, Johann Gottfried Galle, Jupiter, Kobe University, Konstantin Batygin, Kuiper belt, Large Synoptic Survey Telescope, Lawrence Livermore National Laboratory, List of hypothetical Solar System objects, Lowell Observatory, Madrid, Mars, Martian canal, Mercury (planet), Methane, Michael E. Brown, Minor Planet Center, Monthly Notices of the Royal Astronomical Society, NASA, Neptune, New Horizons, New York (state), Newsweek, Oort cloud, Orbit, Orbital eccentricity, Orbital inclination, Orbital node, Palomar Observatory, Pan-STARRS, Percival Lowell, Perturbation (astronomy), Peru, Peter Andreas Hansen, Philip Herbert Cowell, Pierre-Simon Laplace, Pioneer 10, Pioneer 11, Planet, Planet Nine, Planetary system, Planets beyond Neptune, Plutino, Pluto, Precovery, Retrograde and prograde motion, Robert Sutton Harrington, Rogue planet, Roman numerals, Saturn, Scientific American, Scott S. Sheppard, Semi-major and semi-minor axes, Solar System, Super-Earth, Tests of general relativity, The Astronomical Journal, The Astrophysical Journal, The Independent, The New York Times, The Washington Post, Thomas Jefferson Jackson See, Thomas John Hussey, Time-lapse photography, Trans-Neptunian object, Triton (moon), True anomaly, Tyche (hypothetical planet), United States Naval Observatory, University of Hawaii, University of Louisiana at Lafayette, Uranus, Urbain Le Verrier, Variable star, Vesto Slipher, Vishnu, Volatiles, Voyager 1, Voyager 2, Walter Baade, Wide-field Infrared Survey Explorer, William Henry Pickering, Zodiac, 15760 Albion, 177P/Barnard, 90377 Sedna. Expand index (105 more) » « Shrink index
Abbott Lawrence Lowell (December 13, 1856January 6, 1943) was a U.S. educator and legal scholar.
Sol Alan Stern (born November 22, 1957) is an American engineer and planetary scientist.
Albedo (albedo, meaning "whiteness") is the measure of the diffuse reflection of solar radiation out of the total solar radiation received by an astronomical body (e.g. a planet like Earth).
Alexis Bouvard (27 June 1767 – 7 June 1843) was a French astronomer.
The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth.
Apparent retrograde motion is the apparent motion of a planet in a direction opposite to that of other bodies within its system, as observed from a particular vantage point.
An apsis (ἁψίς; plural apsides, Greek: ἁψῖδες) is an extreme point in the orbit of an object.
Arequipa is the capital and largest city of the Arequipa Region and the seat of the Constitutional Court of Peru.
The argument of periapsis (also called argument of perifocus or argument of pericenter), symbolized as ω, is one of the orbital elements of an orbiting body.
Armin Otto Leuschner (January 16, 1868 – April 22, 1953) was an American astronomer and educator.
Asteroids are minor planets, especially those of the inner Solar System.
The astronomical unit (symbol: au, ua, or AU) is a unit of length, roughly the distance from Earth to the Sun.
Astronomy & Astrophysics is a peer-reviewed scientific journal covering theoretical, observational, and instrumental astronomy and astrophysics.
The Atacama Large Millimeter/submillimeter Array (ALMA) is an astronomical interferometer of radio telescopes in the Atacama Desert of northern Chile.
Backyard Worlds: Planet 9 is a NASA-funded citizen science project which is part of the Zooniverse web portal.
A blink comparator was a viewing apparatus used by astronomers to find differences between two photographs of the night sky.
Brahma (Sanskrit: ब्रह्मा, IAST: Brahmā) is a creator god in Hinduism.
Brian Geoffrey Marsden (5 August 1937 – 18 November 2010) was an English astronomer and the longtime director of the Minor Planet Center (MPC) at the Harvard-Smithsonian Center for Astrophysics (director emeritus from 2006 to 2010).
Nicolas Camille Flammarion FRAS (26 February 1842 – 3 June 1925) was a French astronomer and author.
A Cartesian coordinate system is a coordinate system that specifies each point uniquely in a plane by a pair of numerical coordinates, which are the signed distances to the point from two fixed perpendicular directed lines, measured in the same unit of length.
The Cassini–Huygens mission, commonly called Cassini, was a collaboration between NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) to send a probe to study the planet Saturn and its system, including its rings and natural satellites.
Chadwick A. "Chad" Trujillo (born November 22, 1973) is an American astronomer, discoverer of minor planets and the co-discoverer of Eris, the most massive dwarf planet known in the Solar System.
Charon, also known as (134340) Pluto I, is the largest of the five known natural satellites of the dwarf planet Pluto.
Christian Heinrich Friedrich Peters (September 19, 1813 – July 18, 1890) was a German–American astronomer, and a pioneer in the study of asteroids.
Christmas is an annual festival commemorating the birth of Jesus Christ,Martindale, Cyril Charles.
The Christmas season, also called the festive season, or the holiday season (mainly in the U.S. and Canada; often simply called the holidays),, is an annually recurring period recognized in many Western and Western-influenced countries that is generally considered to run from late November to early January.
Christmas Eve is the evening or entire day before Christmas Day, the festival commemorating the birth of Jesus.
Christmas traditions vary from country to country.
Classical mechanics describes the motion of macroscopic objects, from projectiles to parts of machinery, and astronomical objects, such as spacecraft, planets, stars and galaxies.
"Clearing the neighbourhood around its orbit" is a criterion for a celestial body to be considered a planet in the Solar System.
Clyde William Tombaugh (February 4, 1906January 17, 1997) was an American astronomer.
Cable News Network (CNN) is an American basic cable and satellite television news channel and an independent subsidiary of AT&T's WarnerMedia.
A comet is an icy small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called outgassing.
Comet Swift–Tuttle (formally designated 109P/Swift–Tuttle) is a periodic comet with a current (osculating) orbital period of 133 years.
The Complutense University of Madrid (Universidad Complutense de Madrid or Universidad de Madrid, Universitas Complutensis) is a public research university located in Madrid, and one of the oldest universities in the world.
David C. Jewitt (born 1958) is an English astronomer and professor of astronomy at UCLA's Earth, Planetary, and Space Science Department in California.
David Peck Todd (March 19, 1855 – June 1, 1939) was a noted American astronomer.
Detached objects are a dynamical class of minor planets in the outer reaches of the Solar System and belong to the broader family of trans-Neptunian objects (TNOs).
A dwarf planet is a planetary-mass object that is neither a planet nor a natural satellite.
Erland Myles Standish, Jr. (born March 5, 1939) is a mathematical astronomer and a former professor at Yale University.
Earth is the third planet from the Sun and the only astronomical object known to harbor life.
The ecliptic is the circular path on the celestial sphere that the Sun follows over the course of a year; it is the basis of the ecliptic coordinate system.
Ernest William Brown FRS (29 November 1866 – 22 July 1938) was an English mathematician and astronomer, who spent the majority of his career working in the United States and became a naturalised American citizen in 1923.
Europa or as Ευρώπη (Jupiter II) is the smallest of the four Galilean moons orbiting Jupiter, and the sixth-closest to the planet.
The fictional portrayal of our Solar System has often included planets, moons, and other celestial objects which do not actually exist in reality.
Flagstaff is a city in and the county seat of Coconino County in northern Arizona, in the southwestern United States.
A galactic tide is a tidal force experienced by objects subject to the gravitational field of a galaxy such as the Milky Way.
The Galilean moons are the four largest moons of Jupiter—Io, Europa, Ganymede, and Callisto.
Ganymede (Jupiter III) is the largest and most massive moon of Jupiter and in the Solar System.
A gas giant is a giant planet composed mainly of hydrogen and helium.
Sir George Biddell Airy (27 July 18012 January 1892) was an English mathematician and astronomer, Astronomer Royal from 1835 to 1881.
Prof George Forbes FRS FRSE FRAS (5 April 1849 – 22 October 1936) was an electrical engineer, astronomer, explorer, author and inventor, some of whose inventions are still in use.
Gerard Peter Kuiper (born Gerrit Pieter Kuiper; December 7, 1905 – December 23, 1973) was a Dutch–American astronomer, planetary scientist, selenographer, author and professor.
A giant planet is any massive planet.
In Norse mythology, Gná is a goddess who runs errands in other worlds for the goddess Frigg and rides the flying, sea-treading horse Hófvarpnir (Old Norse "he who throws his hoofs about",Simek (2007:157). "hoof-thrower"Lindow (2001:146). or "hoof kicker"Byock (2005:43).). Gná and Hófvarpnir are attested in the Prose Edda, written in the 13th century by Snorri Sturluson.
Gotha is the fifth-largest city in Thuringia, Germany, located west of Erfurt and east of Eisenach with a population of 44,000.
Gotha Observatory (Seeberg Observatory, Sternwarte Gotha or Seeberg-Sternwarte) was a German astronomical observatory located on Seeberg hill near Gotha, Thuringia, Germany.
Halley's Comet or Comet Halley, officially designated 1P/Halley, is a short-period comet visible from Earth every 74–79 years.
Hamilton College is a private, nonsectarian liberal arts college in Clinton, New York.
Hans-Emil Lau (16 April 1879 – 16 October 1918) was a Danish astronomer.
Harlow Shapley (November 2, 1885 – October 20, 1972) was a 20th-century American scientist, head of the Harvard College Observatory (1921–1952), and political activist during the latter New Deal and Fair Deal.
The Harvard College Observatory (HCO) is an institution managing a complex of buildings and multiple instruments used for astronomical research by the Harvard University Department of Astronomy.
Heinrich Louis d'Arrest (13 August 1822 – 14 June 1875) was a German astronomer, born in Berlin.
The International Astronomical Union (IAU) defined in August 2006 that, in the Solar System, a planet is a celestial body which.
Icarus is a scientific journal dedicated to the field of planetary science.
Infrared cirrus are filamentary structures seen in space that emit infrared light.
The International Astronomical Union (IAU; Union astronomique internationale, UAI) is an international association of professional astronomers, at the PhD level and beyond, active in professional research and education in astronomy.
Io (Jupiter I) is the innermost of the four Galilean moons of the planet Jupiter.
The Infrared Astronomical Satellite (IRAS) was the first-ever space telescope to perform a survey of the entire night sky at infrared wavelengths.
Jacques Babinet (5 March 1794 – 21 October 1872) was a French physicist, mathematician, and astronomer who is best known for his contributions to optics.
James Ferguson (August 31, 1797 – September 26, 1867) was a Scottish-born American astronomer and engineer, who made the first discovery of an asteroid from North America (31 Euphrosyne).
James Walter "Jim" Christy (born September 15, 1938) is an American astronomer.
The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in Pasadena, California, United States, with large portions of the campus in La Cañada Flintridge, California.
The name Jet Propulsion Laboratory Development Ephemeris (followed by a number), the abbreviation JPL DE(number), or just DE(number) designates one of a series of models of the Solar System produced at the Jet Propulsion Laboratory in Pasadena, California, primarily for purposes of spacecraft navigation and astronomy.
Johann Gottfried Galle, 1880 Galle's signature Memorial plaque in Wittenberg Johann Gottfried Galle (9 June 1812 – 10 July 1910) was a German astronomer from Radis, Germany, at the Berlin Observatory who, on 23 September 1846, with the assistance of student Heinrich Louis d'Arrest, was the first person to view the planet Neptune and know what he was looking at.
Jupiter is the fifth planet from the Sun and the largest in the Solar System.
, also known in the Kansai region as, is a leading Japanese national university located in the city of Kobe, in Hyōgo.
Konstantin Batygin (Константи́н Юрьевич Батыгин) is a Russian-American astronomer and Assistant Professor of Planetary Sciences at Caltech.
The Kuiper belt, occasionally called the Edgeworth–Kuiper belt, is a circumstellar disc in the outer Solar System, extending from the orbit of Neptune (at 30 AU) to approximately 50 AU from the Sun.
The Large Synoptic Survey Telescope (LSST) is a wide-field survey reflecting telescope with an 8.4-meter primary mirror, currently under construction, that will photograph the entire available sky every few nights.
Lawrence Livermore National Laboratory (LLNL) is an American federal research facility in Livermore, California, United States, founded by the University of California, Berkeley in 1952.
A hypothetical Solar System object is a planet, natural satellite or similar body in the Solar System whose existence is not known, but has been inferred from observational scientific evidence.
Lowell Observatory is an astronomical observatory in Flagstaff, Arizona, United States.
Madrid is the capital of Spain and the largest municipality in both the Community of Madrid and Spain as a whole.
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.
For a time in the late 19th and early 20th centuries, it was erroneously believed that there were canals on Mars.
Mercury is the smallest and innermost planet in the Solar System.
Methane is a chemical compound with the chemical formula (one atom of carbon and four atoms of hydrogen).
Michael E. Brown (born June 5, 1965) is an American astronomer, who has been professor of planetary astronomy at the California Institute of Technology (Caltech) since 2003.
The Minor Planet Center (MPC) is the official worldwide organization in charge of collecting observational data for minor planets (such as asteroids and comets), calculating their orbits and publishing this information via the Minor Planet Circulars.
Monthly Notices of the Royal Astronomical Society (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics.
The National Aeronautics and Space Administration (NASA) is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research.
Neptune is the eighth and farthest known planet from the Sun in the Solar System.
New Horizons is an interplanetary space probe that was launched as a part of NASA's New Frontiers program.
New Year is the time or day at which a new calendar year begins and the calendar's year count increments by one.
New Year's Day, also called simply New Year's or New Year, is observed on January 1, the first day of the year on the modern Gregorian calendar as well as the Julian calendar.
In the Gregorian calendar, New Year's Eve (also known as Old Year's Day or Saint Sylvester's Day in many countries), the last day of the year, is on 31 December which is the seventh day of Christmastide.
New York is a state in the northeastern United States.
Newsweek is an American weekly magazine founded in 1933.
The Oort cloud, named after the Dutch astronomer Jan Oort, sometimes called the Öpik–Oort cloud, is a theoretical cloud of predominantly icy planetesimals proposed to surround the Sun at distances ranging from.
In physics, an orbit is the gravitationally curved trajectory of an object, such as the trajectory of a planet around a star or a natural satellite around a planet.
The orbital eccentricity of an astronomical object is a parameter that determines the amount by which its orbit around another body deviates from a perfect circle.
Orbital inclination measures the tilt of an object's orbit around a celestial body.
An orbital node is either of the two points where an orbit intersects a plane of reference to which it is inclined.
Palomar Observatory is an astronomical observatory located in San Diego County, California, United States, southeast of Los Angeles, California, in the Palomar Mountain Range.
The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS 1; obs. code: F51 and Pan-STARRS 2 obs. code: F52) located at Haleakala Observatory, Hawaii, USA, consists of astronomical cameras, telescopes and a computing facility that is surveying the sky for moving or variable objects on a continual basis, and also producing accurate astrometry and photometry of already detected objects.
Percival Lawrence Lowell (March 13, 1855 – November 12, 1916) was an American businessman, author, mathematician, and astronomer who fueled speculation that there were canals on Mars.
In astronomy, perturbation is the complex motion of a massive body subject to forces other than the gravitational attraction of a single other massive body.
Peru (Perú; Piruw Republika; Piruw Suyu), officially the Republic of Peru, is a country in western South America.
Peter Andreas Hansen (born December 8, 1795 Tønder, Schleswig, Denmark – died March 28, 1874 Gotha, Thuringia, Germany) was a Danish German astronomer.
Philip Herbert Cowell FRS (7 August 1870, Calcutta – 6 June 1949) was a British astronomer.
Pierre-Simon, marquis de Laplace (23 March 1749 – 5 March 1827) was a French scholar whose work was important to the development of mathematics, statistics, physics and astronomy.
Pioneer 10 (originally designated Pioneer F) is an American space probe, launched in 1972 and weighing, that completed the first mission to the planet Jupiter.
Pioneer 11 (also known as Pioneer G) is a robotic space probe launched by NASA on April 6, 1973 to study the asteroid belt, the environment around Jupiter and Saturn, solar wind and cosmic rays.
A planet is an astronomical body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.
Planet Nine is a hypothetical planet in the outer region of the Solar System.
A planetary system is a set of gravitationally bound non-stellar objects in or out of orbit around a star or star system.
Following the discovery of the planet Neptune in 1846, there was considerable speculation that another planet might exist beyond its orbit.
In astronomy, the plutinos are a dynamical group of trans-Neptunian objects in the outermost region of the Solar System that orbit in 2:3 mean-motion resonance with Neptune.
Pluto (minor planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of bodies beyond Neptune.
In astronomy, precovery (short for pre-discovery recovery) is the process of finding the image of an object in old archived images or photographic plates for the purpose of calculating a more accurate orbit.
Retrograde motion in astronomy is, in general, orbital or rotational motion of an object in the direction opposite the rotation of its primary, that is the central object (right figure).
Robert Sutton Harrington (October 21, 1942 – January 23, 1993) was an American astronomer who worked at the United States Naval Observatory (USNO).
A rogue planet (also termed an interstellar planet, nomad planet, free-floating planet, orphan planet, wandering planet, starless planet, or sunless planet) is a planetary-mass object that orbits a galactic center directly.
The numeric system represented by Roman numerals originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages.
Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter.
Scientific American (informally abbreviated SciAm) is an American popular science magazine.
Scott Sander Sheppard (b. 1976) is an American astronomer and a discoverer of numerous moons, comets and minor planets in the outer Solar System.
In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the widest points of the perimeter.
The Solar SystemCapitalization of the name varies.
A super-Earth is an extrasolar planet with a mass higher than Earth's, but substantially below the masses of the Solar System's ice giants, Uranus and Neptune, which have masses of 15 and 17 times Earth's, respectively.
Tests of general relativity serve to establish observational evidence for the theory of general relativity.
The Astronomical Journal (often abbreviated AJ in scientific papers and references) is a peer-reviewed monthly scientific journal owned by the American Astronomical Society and currently published by IOP Publishing.
The Astrophysical Journal, often abbreviated ApJ (pronounced "ap jay") in references and speech, is a peer-reviewed scientific journal of astrophysics and astronomy, established in 1895 by American astronomers George Ellery Hale and James Edward Keeler.
The Independent is a British online newspaper.
The New York Times (sometimes abbreviated as The NYT or The Times) is an American newspaper based in New York City with worldwide influence and readership.
The Washington Post is a major American daily newspaper founded on December 6, 1877.
Thomas Jefferson Jackson (T. J. J.) See (February 19, 1866 – July 4, 1962) was an American astronomer whose promulgated theories in astronomy and physics were eventually disproven.
Thomas John Hussey (4 April 1792 – c. 1866) was an English clergyman and astronomer.
Time-lapse photography is a technique whereby the frequency at which film frames are captured (the frame rate) is much lower than that used to view the sequence.
A trans-Neptunian object (TNO, also written transneptunian object) is any minor planet in the Solar System that orbits the Sun at a greater average distance (semi-major axis) than Neptune, 30 astronomical units (AU).
Triton is the largest natural satellite of the planet Neptune, and the first Neptunian moon to be discovered.
In celestial mechanics, true anomaly is an angular parameter that defines the position of a body moving along a Keplerian orbit.
Tyche is a hypothetical gas giant located in the Solar System's Oort cloud, first proposed in 1999 by astrophysicists John Matese, Patrick Whitman and Daniel Whitmire of the University of Louisiana at Lafayette.
The United States Naval Observatory (USNO) is one of the oldest scientific agencies in the United States, with a primary mission to produce Positioning, Navigation and Timing (PNT) for the United States Navy and the United States Department of Defense.
The University of Hawaiʻi system (formally the University of Hawaiʻi and popularly known as UH) is a public, co-educational college and university system that confers associate, bachelor's, master's, and doctoral degrees through three university campuses, seven community college campuses, an employment training center, three university centers, four education centers and various other research facilities distributed across six islands throughout the State of Hawaii in the United States.
The University of Louisiana at Lafayette (UL Lafayette, ULL, or UL) is a coeducational, public, research university in Lafayette, in the U.S. state of Louisiana.
Uranus is the seventh planet from the Sun.
Urbain Jean Joseph Le Verrier (11 March 1811 – 23 September 1877) was a French mathematician who specialized in celestial mechanics and is best known for predicting the existence and position of Neptune using only mathematics.
A variable star is a star whose brightness as seen from Earth (its apparent magnitude) fluctuates.
Vesto Melvin Slipher (November 11, 1875 – November 8, 1969) was an American astronomer who performed the first measurements of radial velocities for galaxies, providing the empirical basis for the expansion of the universe.
Vishnu (Sanskrit: विष्णु, IAST) is one of the principal deities of Hinduism, and the Supreme Being in its Vaishnavism tradition.
In planetary science, volatiles are the group of chemical elements and chemical compounds with low boiling points that are associated with a planet's or moon's crust or atmosphere.
Voyager 1 is a space probe launched by NASA on September 5, 1977.
Voyager 2 is a space probe launched by NASA on August 20, 1977, to study the outer planets.
Wilhelm Heinrich Walter Baade (March 24, 1893 – June 25, 1960) was a German astronomer who worked in the United States from 1931 to 1959.
Wide-field Infrared Survey Explorer (WISE) is a NASA infrared-wavelength astronomical space telescope launched in December 2009, and placed in hibernation in February 2011.
William Henry Pickering (February 15, 1858 – January 16, 1938) was an American astronomer.
The zodiac is an area of the sky that extends approximately 8° north or south (as measured in celestial latitude) of the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year.
15760 Albion, provisional designation, was the first trans-Neptunian object to be discovered after Pluto and Charon.
Comet 177P/Barnard, also known as Barnard 2, is a periodic comet with an orbital period of 119 years.
2018 has been designated as the third International Year of the Reef by the International Coral Reef Initiative.
2019 (MMXIX) will be a common year starting on Tuesday of the Gregorian calendar, the 2019th year of the Common Era (CE) and Anno Domini (AD) designations, the 19th year of the 3rd millennium, the 19th year of the 21st century, and the 10th and last year of the 2010s decade.
90377 Sedna is a large minor planet in the outer reaches of the Solar System that was,, at a distance of about 86 astronomical units (AU) from the Sun, about three times as far as Neptune.
10th planet, 9th planet, Discovery of Pluto, Halo of oligarch planets, Hypothetical trans-Neptunian planet, Hypothetical trans-Neptunian planets, Ninth planet, Oligarch halo, Oligarch planet, Oligarch planets, Planet 10, Planet O, Planet Ten, Planet X, Planet X (planet), Planet beyond Neptune, Planet beyond neptune, Planet ten, Planet x, Planets beyond Pluto, Planets beyond pluto, Pluto discovery, Sol IX, Sol X, Sol-9, Super-Pluton, Tenth Planet, Tenth planet, The 9th planet, The ninth planet, Thelisto (hypothetical planet), Trans neptunian planets, Trans-Neptunian planet, Trans-Neptunian planets, Trans-neptunian planet, Transpluto, V P Ketakar, V. P. Ketakar, VP Ketakar, Venkatesh Ketakar, Venkatesh P. Ketakar, X (planet).