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Planet Nine

Planet Nine is a hypothetical ninth planet in the outer region of the Solar System. Its gravitational effects could explain the peculiar clustering of orbits for a group of extreme trans-Neptunian objects (ETNOs)—bodies beyond Neptune that orbit the Sun at distances averaging more than 250 times that of the Earth, over 250 astronomical units (AU). These…

History, Geography, Measurement & Art

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Aphelion
370±30 AU
Apparent magnitude
≈21
Argument of perihelion
150° (est.)
Eccentricity
0.29±0.13
Inclination
6.8°±5.0°
Mass
4.4±1.1 M🜨

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Overview

History

Batygin and Brown hypothesis

Alternative hypotheses

Detection attempts

Attempts to predict location

Attempts to predict the semi-major axis

Naming

Advanced semantic analysis

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Map overview Semantic statistics

Planet Nine

Nodes252
Edges251
Triples411
Avg. degree1.99
Density0.007937
Components1

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Planet Nine

Top relations

related to Searches of existing data · 29
Planet Nine → As, AU, Batygin, Berkeley, Brown, California, Catalina Sky Survey, Danny Goldstein, Dark Energy Survey, David Gerdes, Earth, In, Michael Medford, Milky Way, NEOWISE, Other, Pan-STARRS, Planet Nine's, Solar System, The
related to Inclination instability in a massive disk · 28
Planet Nine → An, Ann-Marie Madigan, AU, Earth, Earth-mass, ETNOs, If, In Nice, Instead, LSST, Madigan, Michael McCourt, Mike Brown, Neptunian, Rubin Observatory Legacy Survey, Sedna, Simulations, Solar System, Space, Sun
related to Naming · 26
Planet Nine → Batygin, Bowie's, Brown, Change, Consequently, David Bowie, George, Greek, However, If Planet Nine, In, International Astronomical Union, It, Jehoshaphat, Major Tom, Neptune, Only, Phattie, Pluto, Roman
related to Temporary or coincidental clustering · 26
Planet Nine → After, AU, Batygin, Brown, Cory Shankman, Dark Energy Survey, Earth, ETNOs, He, However, Many, Mike Brown, OSSOS, Outer Solar System Survey, Pedro Bernardinelli, Planet Nine's, Shankman, Sheppard, Simulations, Solar System
related to history · 25
Planet Nine → After, After Voyager, Among, Attempts, AU, Clyde Tombaugh, Earth, Following, Forbes, Gabriel Dallet, George Forbes, He, Jupiter-family, Lowell's, Lowell's Planet, Neptune, Neptunian, One, Percival Lowell, Planet
related to Reception · 21
Planet Nine → All, Astronomer Alessandro Morbidelli, Batygin, Brown, Brown's, But Green, Carl Sagan, ETNOs, Greg Laughlin, In, In January, Jim Green, KBOs, Massachusetts Institute, NASA's Science Mission Directorate, Other, Solar System, Technology Professor Tom Levenson, The Astronomical Journal, The Planet Nine
related to Primordial black hole · 19
Planet Nine → Amir Siraj, Avi Loeb, CMB, Edward Witten, ETNOs, FERMILAT, In, Jakub Scholtz, James Unwin, Konstantin Batygin, OGLE, Rubin Observatory, Since, Solar System, Their, They, Thiem Hoang, This, Vera
related to Attempts to predict the semi-major axis · 18
Planet Nine → Alicanto, An, AU, Batygin's, Brown, Carlos, CR105, ETNOs, FP185, Fuente Marcos, Gregory Laughlin, Kuiper, Neptune, Raúl, Sarah Millholland, Sedna, They, VP113
related to Citizen science · 18
Planet Nine → April, August, Backyard Worlds, Catalina Outer Solar System, Catalina Sky Survey, Center, It, Marc Kuchner, NASA's Goddard Space Flight, NASA-funded, No, Planet, Solar System, Survey, The, The Zooniverse, TNOs, Zooniverse
measured by · 17
Planet Nine → An, At, AU, Batygin, Brown's, Cassini, Cetus, Fienga, Gastineau, In, Laskar, Manche, Precise, Saturn's, Sun, The, This

Important terminology Word statistics

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Important terminology

planet nine objects orbits au orbit would perihelion semi-major etnos solar brown system axis batygin also could observed planets inclination

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Planet NineAphelion370±30 AU1.00infobox
Planet NineApparent magnitude≈211.00infobox
Planet NineArgument of perihelion150° (est.)1.00infobox
Planet NineEccentricity0.29±0.131.00infobox
Planet NineInclination6.8°±5.0°1.00infobox
Planet NineMass4.4±1.1 M🜨1.00infobox
Planet NineOrbital period (sidereal)4,940+790 −750 yr[A]1.00infobox
Planet NinePerihelion200±50 AU1.00infobox
Planet NineSemi-major axis290±30 AU1.00infobox
Planet Nineis ahypothetical ninth planet in the outer region of the Solar System0.90text
Planet Nineis aonly one that explains all four0.90text
Wide-field Infrared Survey Explorerinstance ofor that it formed on a distant orbit and was pulled into an eccentric orbit by a passing star.Although sky surveys0.80text

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