Eris ( dwarf planet ) - Wikipedia Eris ( dwarf planet ) This article is about the dwarf planet. For the asteroid, see 433 Eros. Eris Eris ( center ) and Dysnomia ( left of center ), taken by the Hubble Space Telescope Discovery Discovered by M.E. Brown C.A. Trujillo D.L. Rabinowitz Discovery date January 5, 2005 Designations MPC designation ( 136199 ) Eris Pronunciation / ˈɪərɪs / or / ˈɛrɪs / Named after Eris Alternative designations 2003 UB Minor planet category Dwarf planet TNO Plutoid SDO Binary Adjectives Eridian Orbital characteristics Epoch December 9, 2014 ( JD 7006245700050000000 ♠ 2457000. 5 ) Aphelion 7013146083816717257 ♠ 97.651 AU 7013146020000000000 ♠ 14.602 × 10 km Perihelion 7012567140487610770 ♠ 37.911 AU 7012572300000000000 ♠ 5.723 × 10 km Semi-major axis 7013101398932739167 ♠ 67.781 AU 7013101660000000000 ♠ 10.166 × 10 km Eccentricity 6999440680000000000 ♠ 0.440 68 Orbital period 7010176109120000000 ♠ 203,830 d 7002558039999999999 ♠ 558.04 yr Average orbital speed 7003343380000000000 ♠ 3.4338 km / s Mean anomaly 7000356326420087163 ♠ 204.16 ° Inclination 6999768721542394644 ♠ 44.0445 ° Longitude of ascending node 6999627499971298774 ♠ 35.9531 ° Argument of perihelion 7000263504574478348 ♠ 150.977 ° Known satellites Dysnomia Physical characteristics Mean radius 7006116300000000000 ♠ 1163 ± 6 km Surface area 7013170000000000000 ♠ ( 1.70 ± 0.02 ) × 10 km Volume 7018659000000000000 ♠ ( 6.59 ± 0.10 ) × 10 km Mass 7022166000000000000 ♠ ( 1.66 ± 0.02 ) × 10 kg 0.0028 Earths 0.23 Moons Mean density 7003252000000000000 ♠ 2.52 ± 0.07 g / cm Equatorial surface gravity 6999820000000000000 ♠ 0.82 ± 0.02 m / s 6998830000000000000 ♠ 0.083 ± 0.002 g Equatorial escape velocity 1.38 ± 0.01 km / s Sidereal rotation period 7001259000000000000 ♠ 25.9 ± 0.5 hr Geometric albedo 6999960000000000000 ♠ 0.96 + 0.09 − 0.04 Surface temp. min mean max ( approx ) 30 K 42.5 K 55 K Spectral type B − V = 0.78, V − R = 0.45 Apparent magnitude 18.7 Absolute magnitude ( H ) 2999883000000000000 ♠ − 1.17 + 0.06 − 0.11 Angular diameter 40 milli - arcsec Eris ( minor - planet designation 136199 Eris ) is the most massive and second - largest dwarf planet known in the Solar System. Eris was discovered in January 2005 by a Palomar Observatory - based team led by Mike Brown, and its identity was verified later that year. In September 2006 it was named after Eris, the Greek goddess of strife and discord. Among known bodies of the Solar System, Eris is the ninth most massive directly orbiting the Sun, and the 16th most massive overall, because seven moons are more massive than all known dwarf planets. It is also the largest which has not yet been visited by a spacecraft. Eris was measured to be 2,326 ± 12 kilometers ( 1,445.3 ± 7.5 mi ) in diameter. Eris ' mass is about 0.27 % of the Earth mass, about 27 % more than dwarf planet Pluto, although Pluto is slightly larger by volume. Eris is a trans - Neptunian object ( TNO ) and a member of a high - eccentricity population known as the scattered disk. It has one known moon, Dysnomia. As of February 2016, its distance from the Sun was 96.3 astronomical units ( 1.441 × 10 km ; 8.95 × 10 mi ), roughly three times that of Pluto. With the exception of some long - period comets, Eris and Dysnomia are currently the second-most - distant known natural objects in the Solar System, the farthest object being V774104 discovered in November 2015 at 103 AU. Because Eris appeared to be larger than Pluto, NASA initially described it as the Solar System 's tenth planet. This, along with the prospect of other objects of similar size being discovered in the future, motivated the International Astronomical Union ( IAU ) to define the term planet for the first time. Under the IAU definition approved on August 24, 2006, Eris is a `` dwarf planet '', along with objects such as Pluto, Ceres, Haumea and Makemake, thereby reducing the number of known planets in the Solar System to eight, the same as before Pluto 's discovery in 1930. Observations of a stellar occultation by Eris in 2010 showed that its diameter was 2,326 ± 12 kilometers ( 1,445.3 ± 7.5 mi ), very slightly less than Pluto, which was measured by New Horizons as 2,372 ± 4 kilometers ( 1,473.9 ± 2.5 mi ) in July 2015. Contents 1 History 1.1 Discovery 1.2 Name 1.2. 1 Xena 1.2. 2 Choosing an official name 2 Classification 3 Orbit 4 Size, mass and density 5 Surface and atmosphere 6 Satellite 7 Exploration 8 See also 9 Notes 10 References 11 External links History Discovery Animation showing the movement of Eris on the images used to discover it. Eris is indicated by the arrow. The three frames were taken over a period of three hours. Eris was discovered by the team of Mike Brown, Chad Trujillo, and David Rabinowitz on January 5, 2005, from images taken on October 21, 2003. The discovery was announced on July 29, 2005, the same day as Makemake and two days after Haumea, due in part to events that would later lead to controversy about Haumea. The search team had been systematically scanning for large outer Solar System bodies for several years, and had been involved in the discovery of several other large TNOs, including 50000 Quaoar, 90482 Orcus, and 90377 Sedna. Routine observations were taken by the team on October 21, 2003, using the 1.2 m Samuel Oschin Schmidt telescope at Palomar Observatory, California, but the image of Eris was not discovered at that point due to its very slow motion across the sky : The team 's automatic image - searching software excluded all objects moving at less than 1.5 arcseconds per hour to reduce the number of false positives returned. When Sedna was discovered, it was moving at 1.75 arcsec / h, and in light of that the team reanalyzed their old data with a lower limit on the angular motion, sorting through the previously excluded images by eye. In January 2005, the re-analysis revealed Eris 's slow motion against the background stars. Follow - up observations were then carried out to make a preliminary determination of Eris 's orbit, which allowed the object 's distance to be estimated. The team had planned to delay announcing their discoveries of the bright objects Eris and Makemake until further observations and calculations were complete, but announced them both on July 29 when the discovery of another large TNO they had been tracking, Haumea, was controversially announced on July 27 by a different team in Spain. More observations released in October 2005 revealed that Eris has a moon, later named Dysnomia. Observations of Dysnomia 's orbit permitted scientists to determine the mass of Eris, which in June 2007 they calculated to be 7022166000000000000 ♠ ( 1.66 ± 0.02 ) × 10 kg, 6999270000000000000 ♠ 27 % ± 2 % greater than Pluto 's. Name Athenian painting of Eris, c. 550 BC Eris is named after the Greek goddess Eris ( Greek Ἔρις ), a personification of strife and discord. The name was assigned on September 13, 2006, following an unusually long period in which the object was known by the provisional designation 2003 UB, which was granted automatically by the IAU under their naming protocols for minor planets. The regular adjectival form of Eris is Eridian. Xena Due to uncertainty over whether the object would be classified as a planet or a minor planet, because different nomenclature procedures apply to these different classes of objects, the decision on what to name the object had to wait until after the August 24, 2006, IAU ruling. As a result, for a time the object became known to the wider public as Xena. `` Xena '' was an informal name used internally by the discovery team. It was inspired by the title character of the television series Xena : Warrior Princess. The discovery team had reportedly saved the nickname `` Xena '' for the first body they discovered that was larger than Pluto. According to Brown, We chose it since it started with an X ( planet `` X '' ), it sounds mythological ( OK, so it 's TV mythology, but Pluto is named after a cartoon, right ? ), and ( this part is actually true ) we 've been working to get more female deities out there ( e.g. Sedna ). Also, at the time, the TV show was still on TV, which shows you how long we 've been searching ! `` We assumed ( that ) a real name would come out fairly quickly, ( but ) the process got stalled '', Mike Brown said in interview, One reporter ( Ken Chang ) called me up from the New York Times who happened to have been a friend of mine from college, ( and ) I was a little less guarded with him than I am with the normal press. He asked me, `` What 's the name you guys proposed ? '' and I said, `` Well, I 'm not going to tell. '' And he said, `` Well, what do you guys call it when you 're just talking amongst yourselves ? ''... As far as I remember this was the only time I told anybody this in the press, and then it got everywhere, which I only sorta felt bad about -- I kinda like the name. Choosing an official name Artist 's impression of the dwarf planet Eris and its large moon Dysnomia. This artistic representation is based on observations made at ESO 's La Silla Observatory. According to science writer Govert Schilling, Brown initially wanted to call the object `` Lila '', after a concept in Hindu mythology that described the cosmos as the outcome of a game played by Brahma. The name was very similar to `` Lilah '', the name of Brown 's newborn daughter. Brown was mindful of not making his name public before it had been officially accepted. He had done so with Sedna a year previously, and had been heavily criticized. However, no objection was raised to the Sedna name other than the breach of protocol, and no competing names were suggested for Sedna. He listed the address of his personal web page announcing the discovery as / ~ mbrown / planetlila and in the chaos following the controversy over the discovery of Haumea, forgot to change it. Rather than needlessly anger more of his fellow astronomers, he simply said that the webpage had been named for his daughter and dropped `` Lila '' from consideration. Brown had also speculated that Persephone, the wife of the god Pluto, would be a good name for the object. The name had been used several times in science fiction, and was popular with the public, having handily won a poll conducted by New Scientist magazine ( `` Xena '', despite only being a nickname, came fourth ). This was not possible once the object was classified as a dwarf planet, because there is already an asteroid with that name, 399 Persephone. With the dispute resolved, the discovery team proposed Eris on September 6, 2006. On September 13, 2006 this name was accepted as the official name by the IAU. Brown decided that, because the object had been considered a planet for so long, it deserved a name from Greek or Roman mythology, like the other planets. The asteroids had taken the vast majority of Graeco - Roman names. Eris, whom Brown described as his favorite goddess, had fortunately escaped inclusion. The name in part reflects the discord in the astronomical community caused by the debate over the object 's ( and Pluto 's ) classification. Classification Distribution of trans - Neptunian objects Eris is a trans - Neptunian dwarf planet ( plutoid ). Its orbital characteristics more specifically categorize it as a scattered - disk object ( SDO ), or a TNO that has been `` scattered '' from the Kuiper belt into more - distant and unusual orbits following gravitational interactions with Neptune as the Solar System was forming. Although its high orbital inclination is unusual among the known SDOs, theoretical models suggest that objects that were originally near the inner edge of the Kuiper belt were scattered into orbits with higher inclinations than objects from the outer belt. Inner - belt objects are expected to be generally more massive than outer - belt objects, and so astronomers expect to discover more large objects like Eris in high - inclination orbits, which have traditionally been neglected. Because Eris was initially thought to be larger than Pluto, it was described as the `` tenth planet '' by NASA and in media reports of its discovery. In response to the uncertainty over its status, and because of ongoing debate over whether Pluto should be classified as a planet, the IAU delegated a group of astronomers to develop a sufficiently precise definition of the term planet to decide the issue. This was announced as the IAU 's Definition of a Planet in the Solar System, adopted on August 24, 2006. At this time, both Eris and Pluto were classified as dwarf planets, a category distinct from the new definition of planet. Brown has since stated his approval of this classification. The IAU subsequently added Eris to its Minor Planet Catalogue, designating it ( 136199 ) Eris. Orbit The orbit of Eris ( blue ) compared to those of Saturn, Uranus, Neptune, and Pluto ( white / gray ). The arcs below the ecliptic are plotted in darker colors, and the red dot is the Sun. The diagram on the left is a polar view whereas the diagrams on the right are different views from the ecliptic. Eris has an orbital period of 558 years. Its maximum possible distance from the Sun ( aphelion ) is 97.65 AU, and its closest ( perihelion ) is 37.91 AU. It came to perihelion between 1698 and 1699, to aphelion around 1977, and will return to perihelion around 2256 to 2258. Eris and its moon are currently the second most distant known objects in the Solar System, after V774104, apart from long - period comets and space probes. Approximately forty known TNOs, most notably 2006 SQ 372, 2000 OO and Sedna, though currently closer to the Sun than Eris, have greater average orbital distances than Eris 's semimajor axis of 67.7 AU. Eris 's orbit is highly eccentric, and brings Eris to within 37.9 AU of the Sun, a typical perihelion for scattered objects. This is within the orbit of Pluto, but still safe from direct interaction with Neptune ( 29.8 -- 30.4 AU ). Pluto, on the other hand, like other plutinos, follows a less inclined and less eccentric orbit and, protected by orbital resonance, can cross Neptune 's orbit. It is possible that Eris is in a 17 : 5 resonance with Neptune, though further observations will be required to check that hypothesis. Unlike the eight planets, whose orbits all lie roughly in the same plane as the Earth 's, Eris 's orbit is highly inclined : It is tilted at an angle of about 44 degrees to the ecliptic. In about 800 years, Eris will be closer to the Sun than Pluto for some time ( see the graph at the right ). The distances of Eris and Pluto from the Sun in the next 1,000 years As of February 2016, Eris has an apparent magnitude of 18.7, making it bright enough to be detectable to some amateur telescopes. A 200 - millimeter ( 7.9 in ) telescope with a CCD can detect Eris under favorable conditions. The reason it had not been noticed until now is its steep orbital inclination ; searches for large outer Solar System objects tend to concentrate on the ecliptic plane, where most bodies are found. Because of the high inclination of its orbit, Eris only passes through a few constellations of the traditional Zodiac ; it is now in the constellation Cetus. It was in Sculptor from 1876 until 1929 and Phoenix from roughly 1840 until 1875. In 2036 it will enter Pisces and stay there until 2065, when it will enter Aries. It will then move into the northern sky, entering Perseus in 2128 and Camelopardalis ( where it will reach its northernmost declination ) in 2173. Most - distant known objects in the Solar System as of 25 August 2017 Object name Distance from the Sun ( AU ) Apparent magnitude Absolute magnitude ( H ) Current Perihelion Aphelion V774104 103 Unknown Unknown 24 Eris 96.19 37.8 97.6 18.7 − 1.1 2014 UZ 224 91.22 38.0 179.8 23.2 3.5 2007 OR 87.81 33.0 100.8 21.7 1.8 Sedna 85.33 76.0 939 21.0 1.5 2013 FS 28 85.27 34.6 347.6 24.5 4.9 2014 FC 69 84.56 40.3 106.9 24.1 4.6 2006 QH 181 83.72 37.8 96.7 23.6 4.3 2012 VP 113 83.54 80.5 438 23.4 4.0 2013 FY 27 80.13 36.1 81.8 22.1 3.0 2010 GB 174 71.53 48.7 693 25.1 6.5 2014 FJ 72 70.87 38.7 152.2 24.2 5.6 2012 FH 84 68.68 45.8 80.6 25.7 7.3 2015 GR 50 68.33 35.6 78.6 25.1 6.7 2015 GP 50 67.99 35.9 89.1 24.8 6.5 2013 FQ 28 67.63 48.7 80.6 24.4 6.0 2013 UJ 15 64.93 36.3 69.2 25.2 7.0 2014 FL 72 64.10 38.2 170.4 25.0 6.8 2011 GM 89 63.83 37.2 68.8 25.6 7.1 2015 RR 245 63.58 33.7 129.2 22.1 3.9 2014 SU 349 62.55 30.8 109.8 25.0 7.0 2013 AT 183 62.39 36.0 88.1 22.0 4.7 2014 SV 349 61.97 34.2 89.0 23.0 5.0 2014 FE 72 61.58 36.3 4274.0 24.1 6.1 2015 RX 245 61.38 45.5 768.9 24.2 6.2 2000 CR 61.24 44.3 412 23.9 6.3 2008 ST 291 60.44 42.4 154.5 22.2 4.2 2014 FM 72 60.20 34.4 76.6 24.1 6.2 2014 FF 72 60.09 37.1 63.3 24.8 6.9 2003 QX 113 60.04 36.7 62.1 22.5 4.7 2015 KH 162 59.45 41.5 82.8 21.6 3.9 2013 UT 15 59.30 43.9 347.9 24.2 6.3 2014 FL 70 59.24 33.1 77.0 24.0 6.5 2013 SY 99 59.13 49.9 1301.4 24.5 6.8 2014 FH 72 59.06 37.3 77.3 25.1 7.2 This table includes all known objects currently located at least twice as far as Neptune. See List of trans - Neptunian objects for more. view talk Size, mass and density Size estimates Year Radius ( diameter ) Source 2005 1,199 ( 2,397 ) km Hubble 2007 1,300 ( 2,600 ) km Spitzer 2011 1,163 ( 2,326 ) km Occultation In 2005, the diameter of Eris was measured to be 7006239700000000000 ♠ 2397 ± 100 km, using images from the Hubble Space Telescope ( HST ). The size of an object is determined from its absolute magnitude ( H ) and the albedo ( the amount of light it reflects ). At a distance of 97 AU, an object with a diameter of 3,000 km would have an angular size of 40 milliarcseconds, which is directly measurable with the Hubble Space Telescope. Although resolving such small objects is at the very limit of its capabilities, sophisticated image processing techniques such as deconvolution can be used to measure such angular sizes fairly accurately. Artistic comparison of Pluto, Eris, Makemake, Haumea, Sedna, 2007 OR, Quaoar, Orcus, and Earth along with the Moon. This makes Eris around the same size as Pluto, which is 7006237200000000000 ♠ 2372 ± 4 km across. It also indicates an albedo of 0.96, higher than that of any other large body in the Solar System except Enceladus. It is speculated that the high albedo is due to the surface ices being replenished because of temperature fluctuations as Eris 's eccentric orbit takes it closer and farther from the Sun. In 2007, a series of observations of the largest trans - Neptunian objects with the Spitzer Space Telescope gave an estimate of Eris 's diameter of 7006260000000000000 ♠ 2600 + 400 − 200 km. The Spitzer and Hubble estimates overlap in the range of 2,400 -- 2,500 km, 4 -- 8 % larger than Pluto. Astronomers now suspect that Eris 's spin axis is currently pointing toward the Sun, which would make the sunlit hemisphere warmer than average and skew any infrared measurements toward higher values. So the outcome from the 2010 Chile occultation is actually more in line with the Hubble result from 2005. In November 2010, Eris was the subject of one of the most distant stellar occultations yet from Earth. Preliminary data from this event cast doubt on previous size estimates. The teams announced their final results from the occultation in October 2011, with an estimated diameter of 7006232600000000000 ♠ 2326 + 6 − 6 km. The mass of Eris can be calculated with much greater precision. Based on the currently accepted value for Dysnomia 's period -- 15.774 days -- Eris is 27 percent more massive than Pluto. If the 2011 occultation results are used, then Eris has a density of 7003252000000000000 ♠ 2.52 ± 0.07 g / cm, substantially denser than Pluto, and thus must be composed largely of rocky materials. Models of internal heating via radioactive decay suggest that Eris could have an internal ocean of liquid water at the mantle -- core boundary. In July 2015, after nearly ten years of Eris being considered the ninth - largest object known to directly orbit the sun, close - up imagery from the New Horizons mission more accurately determined Pluto 's volume to be slightly larger than Eris 's, rather than slightly smaller as previously thought. Eris is now the tenth - largest object known to directly orbit the sun by volume, though not by mass. Surface and atmosphere The infrared spectrum of Eris, compared to that of Pluto, shows the marked similarities between the two bodies. Arrows denote methane absorption lines. The discovery team followed up their initial identification of Eris with spectroscopic observations made at the 8 m Gemini North Telescope in Hawaii on January 25, 2005. Infrared light from the object revealed the presence of methane ice, indicating that the surface may be similar to that of Pluto, which at the time was the only TNO known to have surface methane, and of Neptune 's moon Triton, which also has methane on its surface. No surface details can be resolved from Earth or its orbit with any instrument currently available. Due to Eris 's distant eccentric orbit, its surface temperature is estimated to vary between about 30 and 56 K ( − 243.2 and − 217.2 ° C ). Unlike the somewhat reddish Pluto and Triton, Eris appears almost white. Pluto 's reddish color is thought to be due to deposits of tholins on its surface, and where these deposits darken the surface, the lower albedo leads to higher temperatures and the evaporation of methane deposits. In contrast, Eris is far enough from the Sun that methane can condense onto its surface even where the albedo is low. The condensation of methane uniformly over the surface reduces any albedo contrasts and would cover up any deposits of red tholins. Even though Eris can be up to three times farther from the Sun than Pluto, it approaches close enough that some of the ices on the surface might warm enough to sublime. Because methane is highly volatile, its presence shows either that Eris has always resided in the distant reaches of the Solar System, where it is cold enough for methane ice to persist, or that the celestial body has an internal source of methane to replenish gas that escapes from its atmosphere. This contrasts with observations of another discovered TNO, Haumea, which reveal the presence of water ice but not methane. Satellite Main article : Dysnomia ( moon ) In 2005, the adaptive optics team at the Keck telescopes in Hawaii carried out observations of the four brightest TNOs ( Pluto, Makemake, Haumea, and Eris ), using the newly commissioned laser guide star adaptive optics system. Images taken on September 10 revealed a moon in orbit around Eris. In keeping with the `` Xena '' nickname already in use for Eris, Brown 's team nicknamed the moon `` Gabrielle '', after the television warrior princess ' sidekick. When Eris received its official name from the IAU, the moon received the name Dysnomia, after the Greek goddess of lawlessness who was Eris 's daughter. Brown says he picked it for similarity to his wife 's name, Diane. The name also retains an oblique reference to Eris 's old informal name Xena, portrayed on TV by Lucy Lawless. Exploration It was calculated that a flyby mission to Eris could take 24.66 years using a Jupiter gravity assist, based on launch dates of 3 April 2032 or 7 April 2044. Eris would be 92.03 or 90.19 AU from the Sun when the spacecraft arrives. See also Solar System portal Book : Dwarf Planets of the Solar System & Their Satellites Book : Solar System Clearing the neighbourhood Former classification of planets List of Solar System objects most distant from the Sun in 2015 List of trans - Neptunian objects Notes Jump up ^ Images were taken on October 21, 2003 ; the object was not detected and identified until 2005. Jump up ^ Both are common ; the former is the literary pronunciation of the name, but Brown and his students use the latter. ^ Jump up to : Calculated from the mean radius ^ Jump up to : Calculated by dividing the listed mass by the listed volume ^ Jump up to : Calculated based on the known parameters Jump up ^ Calculated from the listed diameter ( D ) and albedo ( p ) using H = − 5 log ⁡ D p 1329 ( displaystyle H = - 5 log ( D ( sqrt ( p ) ) over 1329 ) ) Jump up ^ As of February 2016, Sedna is 85.7 astronomical units ( 1.282 × 10 km ; 7.97 × 10 mi ) from the Sun, whereas Eris is 96.3 astronomical units ( 1.441 × 10 km ; 8.95 × 10 mi ) from the Sun. Eris is still close to its 1977 aphelion ( furthest distance from the Sun ), whereas Sedna is nearing its 2076 perihelion ( closest approach to the Sun ). Sedna will overtake Eris as the farthest presently known spherical minor planet in 2114. Jump up ^ Brown is joking on this point. It was in fact the Disney character Pluto that was named after the newly discovered `` planet '', though Venetia Phair, Pluto 's christener, had to counter accusations her whole life that she named the planet after a cartoon dog. Jump up ^ For an example of an amateur image of Eris, see Fred Bruenjes ' Astronomy Jump up ^ The Resolution of the High Resolution Channel of the ACS is 40 marcsec ( milliarcseconds ) and the size of 1 pixel is ~ 25 marcsec i.e. ~ 1875 km at the distance of Eris. Jump up ^ The reference to ' direct ' measurement by the HST should not mislead into thinking that this method is as ' direct ' and model - independent as measuring say Neptune 's size. Basically, the method consists in finding the statistically best fit to a smeared image of the size of less than 2 pixels by comparing it with smeared images of the background stars, using a given computer model of the optics ( PSF ). A non-technical description of the method is given on Brown 's page, a detailed description of this approach and its limitations are discussed in a paper on Quaoar References Jump up ^ Staff ( May 1, 2007 ). `` Discovery Circumstances : Numbered Minor Planets ''. IAU : Minor Planet Center. Retrieved May 5, 2007. ^ Jump up to : Brown, Mike ( 2006 ). `` The discovery of 2003 UB313 Eris, the largest known dwarf planet ''. Retrieved May 3, 2007. ^ Jump up to : `` JPL Small - Body Database Browser : 136199 Eris ( 2003 UB313 ) '' ( September 18, 2014 last obs ). Retrieved November 23, 2014. ^ Jump up to : `` List Of Centaurs and Scattered - Disk Objects ''. Minor Planet Center. Retrieved September 10, 2008. ^ Jump up to : Buie, Marc ( November 6, 2007 ). `` Orbit Fit and Astrometric record for 136199 ''. Deep Ecliptic Survey. Retrieved December 8, 2007. Jump up ^ `` Define Eris ''. Dictionary.com. Random House. Retrieved October 4, 2012. Jump up ^ `` Julia Sweeney and Michael E. Brown ''. Hammer Conversations : KCET podcast. 2007. Archived from the original on October 6, 2008. Retrieved October 1, 2008. ^ Jump up to : Sicardy, B. ; Ortiz, J.L. ; Assafin, M. ; Jehin, E. ; Maury, A. ; Lellouch, E. ; Gil - Hutton, R. ; Braga - Ribas, F. ; Colas, F. ; Widemann ( 2011 ). `` Size, density, albedo and atmosphere limit of dwarf planet Eris from a stellar occultation '' ( PDF ). European Planetary Science Congress Abstracts. 6 : 137. Bibcode : 2011epsc. conf... 137S. Retrieved September 14, 2011. ^ Jump up to : Beatty, Kelly ( November 2010 ). `` Former ' tenth planet ' may be smaller than Pluto ''. NewScientist.com. Sky and Telescope. Retrieved October 17, 2011. ^ Jump up to : Brown, Michael E. ; Schaller, Emily L. ( 15 June 2007 ). `` The Mass of Dwarf Planet Eris '' ( PDF ). Science. 316 ( 5831 ) : 1585. Bibcode : 2007Sci... 316.1585 B. PMID 17569855. doi : 10.1126 / science. 1139415. ^ Jump up to : Johnston, Wm. Robert ( 20 September 2014 ). `` ( 136199 ) Eris and Dysnomia ''. Johnston 's Archive. Retrieved 27 September 2015. Jump up ^ Snodgrass, C. ; Carry, B. ; Dumas, C. ; Hainaut, O. ( February 2010 ). `` Characterisation of candidate members of ( 136108 ) Haumea 's family ''. Astronomy and Astrophysics. 511 : A72. Bibcode : 2010A&A... 511A... 72S. arXiv : 0912.3171. doi : 10.1051 / 0004 - 6361 / 200913031. ^ Jump up to : `` AstDys ( 136199 ) Eris Ephemerides ''. Department of Mathematics, University of Pisa, Italy. Retrieved February 28, 2016. Jump up ^ `` Conversion of Absolute Magnitude to Diameter ''. sfasu.edu. Archived from the original on March 23, 2010. ^ Jump up to : Bertoldi, F. ; Altenhoff, W. ; Weiss, A. ; Menten, K.M. ; Thum, C. ( 2 February 2006 ). `` The trans - Neptunian object UB is larger than Pluto ''. Nature. 439 ( 7076 ) : 563 -- 564. Bibcode : 2006Natur. 439... 563B. PMID 16452973. doi : 10.1038 / nature04494. 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Archived from the original on August 20, 2006. Retrieved August 16, 2006. Jump up ^ Brown, Mike ( 2010 ). `` The shadowy hand of Eris ''. Mike Brown 's Planets. Retrieved November 7, 2010. Jump up ^ Brown, Mike ( November 22, 2010 ). `` How big is Pluto, anyway ? ''. Mike Brown 's Planets. Retrieved November 23, 2010. ( Franck Marchis on 2010 - 11 - 08 ) Jump up ^ `` How Big Is Pluto ? New Horizons Settles Decades - Long Debate ''. NASA. 2015. Retrieved 2015 - 07 - 13. Jump up ^ Thomas H. Maugh II ; John Johnson Jr. ( October 16, 2005 ). `` His Stellar Discovery Is Eclipsed ''. Los Angeles Times. Retrieved July 14, 2008. Jump up ^ Blue, Jennifer ( September 14, 2006 ). `` 2003 UB 313 named Eris ''. USGS Astrogeology Research Program. Retrieved January 3, 2007. Jump up ^ `` International Astronomical Association homepage ''. Archived from the original on September 30, 2007. Retrieved January 5, 2007. ^ Jump up to : Green, Daniel W.E. ( September 13, 2006 ). `` ( 134340 ) Pluto, ( 136199 ) Eris, and ( 136199 ) Eris I ( Dysnomia ) '' ( PDF ). IAU Circular. 8747. Archived from the original on February 5, 2007. Retrieved January 12, 2012. Jump up ^ `` The girl who named a planet ''. BBC News. January 13, 2006. Retrieved June 21, 2007. Jump up ^ `` Xena and Gabrielle '' ( PDF ). Status. January 2006. Retrieved May 3, 2007. Jump up ^ Mike Brown ( 2012 ). How I Killed Pluto and Why It Had It Coming. Spiegel & Grau. p. 159. ^ Jump up to : Brown, Mike ( 2007 ). `` Lowell Lectures in Astronomy ''. WGBH. Archived from the original on July 16, 2008. Retrieved July 13, 2008. Jump up ^ `` Faraway Eris is Pluto 's Twin ''. ESO Science Release. October 26, 2011. Retrieved October 28, 2011. Jump up ^ `` Mpc 52733 '' ( PDF ). Minor Planet Center. 2004. Retrieved 2010 - 08 - 30. Jump up ^ Schilling, Govert ( 2008 ). The Hunt For Planet X. Springer. p. 214. ISBN 978 - 0 - 387 - 77804 - 4. Jump up ^ `` Planet X Marks the Spot '' ( PDF ). TechRepublic. 2006. Retrieved July 13, 2008. Jump up ^ O'Neill, Sean ( 2005 ). `` Your top 10 names for the tenth planet ''. NewScientist. Retrieved June 28, 2008. Jump up ^ `` The Discovery of Eris, the Largest Known Dwarf Planet ''. California Institute of Technology, Department of Geological Sciences. Retrieved January 5, 2007. Jump up ^ `` IAU0605 : IAU Names Dwarf Planet Eris ''. International Astronomical Union News. September 14, 2006. Archived from the original on January 4, 2007. Retrieved January 5, 2007. Jump up ^ `` Pluto Now Called a Plutoid ''. Space.com. June 11, 2008. Retrieved June 11, 2008. Jump up ^ Gomes R.S. ; Gallardo T. ; Fernández J.A. ; Brunini A. ( 2005 ). `` On the origin of the High - Perihelion Scattered Disk : the role of the Kozai mechanism and mean motion resonances ''. Celestial Mechanics and Dynamical Astronomy. 91 ( 1 -- 2 ) : 109 -- 129. Bibcode : 2005CeMDA... 91... 109G. doi : 10.1007 / s10569 - 004 - 4623 - y. Jump up ^ `` NASA - Funded Scientists Discover Tenth Planet ''. Jet Propulsion Laboratory. 2005. Retrieved May 3, 2007. Jump up ^ `` IAU 2006 General Assembly : Resolutions 5 and 6 '' ( PDF ). IAU. August 24, 2006. Archived from the original ( PDF ) on 2006 - 09 - 28. Jump up ^ Robert Roy Britt ( 2006 ). `` Pluto Demoted : No Longer a Planet in Highly Controversial Definition ''. space.com. Retrieved May 3, 2007. ^ Jump up to : Yeomans, Donald K. `` Horizons Online Ephemeris System ''. California Institute of Technology, Jet Propulsion Laboratory. Retrieved January 5, 2007. Jump up ^ Peat, Chris. `` Spacecraft escaping the Solar System ''. Heavens - Above. Retrieved January 25, 2008. Jump up ^ Simulation of Eris ( 2003 UB ) 's orbit predicting a 17 : 5 resonance ^ Jump up to : `` Hubble Finds ' Tenth Planet ' Slightly Larger Than Pluto ''. NASA. April 11, 2006. Retrieved August 29, 2008. ^ Jump up to : John Stansberry ; Will Grundy ; Mike Brown ; John Spencer ; David Trilling ; Dale Cruikshank ; Jean - Luc Margot ( 2007 ). `` Physical Properties of Kuiper Belt and Centaur Objects : Constraints from Spitzer Space Telescope ''. arXiv : astro - ph / 0702538 ( astro - ph ). Jump up ^ `` Comment on the recent Hubble Space Telescope size measurement of 2003 UB313 by Brown et al. ''. Max Planck Institute. 2006. Retrieved May 3, 2007. Jump up ^ M.E. Brown and C.A. Trujillo ( 2004 ). `` Direct Measurement of the Size of the Large Kuiper Belt Object ( 50000 ) Quaoar '' ( PDF ). The Astronomical Journal. 127 ( 7076 ) : 2413 -- 2417. Bibcode : 2004AJ... 127.2413 B. doi : 10.1086 / 382513. Describing in detail the method applied to the recent measure of 2003 UB. Jump up ^ M.E. Brown, E.L. Schaller, H.G. Roe, D.L. Rabinowitz, C.A. Trujillo ( 2006 ). `` Direct measurement of the size of 2003 UB313 from the Hubble Space Telescope '' ( PDF ). The Astrophysical Journal. 643 ( 2 ) : L61 -- L63. Bibcode : 2006ApJ... 643L... 61B. arXiv : astro - ph / 0604245. doi : 10.1086 / 504843. CS1 maint : Multiple names : authors list ( link ) Jump up ^ Brown, Mike ( 2007 ). `` Dysnomia, the moon of Eris ''. Caltech. Retrieved June 14, 2007. Jump up ^ Hussmann, Hauke ; Sohl, Frank ; Spohn, Tilman ( November 2006 ). `` Subsurface oceans and deep interiors of medium - sized outer planet satellites and large trans - neptunian objects '' ( PDF ). Icarus. 185 ( 1 ) : 258 -- 273. Bibcode : 2006Icar... 185... 258H. doi : 10.1016 / j. icarus. 2006.06. 005. Jump up ^ NBC News ( July 13, 2015 ). `` New Horizons Probe Finds Out Pluto 's Bigger ( and Icier ) Than We Thought ''. Retrieved July 13, 2015. Jump up ^ `` Gemini Observatory Shows That `` 10th Planet '' Has a Pluto - Like Surface ``. Gemini Observatory. 2005. Retrieved May 3, 2007. Jump up ^ M.E. Brown, C.A. Trujillo, D.L. Rabinowitz ( 2005 ). `` Discovery of a Planetary - sized Object in the Scattered Kuiper Belt ''. The Astrophysical Journal. 635 ( 1 ) : L97 -- L100. Bibcode : 2005ApJ... 635L... 97B. arXiv : astro - ph / 0508633. doi : 10.1086 / 499336. CS1 maint : Multiple names : authors list ( link ) Jump up ^ J. Licandro ; W.M. Grundy ; N. Pinilla - Alonso ; P. Leisy ( 2006 ). `` Visible spectroscopy of 2003 UB : evidence for N ice on the surface of the largest TNO '' ( PDF ). Astronomy and Astrophysics. 458 ( 1 ) : L5 -- L8. Bibcode : 2006A&A... 458L... 5L. arXiv : astro - ph / 0608044. doi : 10.1051 / 0004 - 6361 : 20066028. Jump up ^ Brown, M.E. ; Van Dam, M.A. ; Bouchez, A.H. ; Le Mignant, D. ; Campbell, R.D. ; Chin, J.C.Y. ; Conrad, A. ; Hartman, S.K. ; Johansson, E.M. ; Lafon, R.E. ; Rabinowitz, D.L. Rabinowitz ; Stomski, P.J., Jr. ; Summers, D.M. ; Trujillo, C.A. ; Wizinowich, P.L. ( 2006 ). `` Satellites of the Largest Kuiper Belt Objects '' ( PDF ). The Astrophysical Journal. 639 ( 1 ) : L43 -- L46. Bibcode : 2006ApJ... 639L... 43B. arXiv : astro - ph / 0510029. doi : 10.1086 / 501524. Retrieved 2011 - 10 - 19. Jump up ^ Tytell, David ( 2006 ). `` All Hail Eris and Dysnomia ''. Sky and Telescope. Retrieved January 5, 2010. Jump up ^ McGranaghan, R. ; Sagan, B. ; Dove, G. ; Tullos, A. ; Lyne, J.E. ; Emery, J.P. ( 2011 ). `` A Survey of Mission Opportunities to Trans - Neptunian Objects ''. Journal of the British Interplanetary Society. 64 : 296 -- 303. Bibcode : 2011JBIS... 64... 296M. External links Wikimedia Commons has media related to Eris. MPC Database entry for ( 136199 ) Eris Michael Brown 's webpage about Eris Brown 's webpage about Dysnomia 2007 KCET interview of Mike Brown about Eris and Haumea with Julia Sweeney compiled list of data MPEC listing for 2003 UB Java 3D orbit visualization Spaceflight Now article about 2003 UB ( Eris ), 2003 EL, and 2005 FY ( Makemake ) Slacker Astronomy Interview With Co-Discoverer Trujillo Trans - Neptunian Object 2003 UB -- IAU statement regarding the planetary status of Eris Simulation of 2003 UB 's orbit Keck observatory page about the discovery of Dysnomia Caltech Press Release, 7 / 29 / 2005 `` Planetary Scientists Discover Tenth Planet ''. Press release on the Spitzer Space Telescope trying to image 2003 UB again Eris Discovery Mike Brown Chad Trujillo David Rabinowitz Samuel Oschin telescope Palomar Observatory Moons Dysnomia Classification Planet Dwarf planet Definition of planet 2006 definition of planet Kuiper belt Trans - Neptunian object Other topics Tenth planet Reflecting telescope Minor planets navigator ( 136198 ) 2003 UJ296 ( 136199 ) Eris ( 136200 ) 2003 VS5 Dwarf planets Asteroid belt IAU : Ceres No longer rounded and therefore not dwarf planets ( Former candidates : Pallas Vesta Hygiea ) Centaurs Possibly : Chariklo Chiron Centaurs ( extended ) Possibly : 1995 SN 55 ( lost ) Ceto 2010 TY 53 Plutinos IAU : Pluto Additional objects proposed by Brown and Tancredi : Orcus Ixion 2003 AZ 2004 UX Huya Possibly : 2003 UZ 2003 VS 2002 VR 2004 PF 2002 XV 93 2007 JH 43 2001 QF 298 Twotinos Possibly : 2002 WC Other resonances / unknown resonances : IAU : Haumea Possibly : 2002 XW 1999 DE 1999 KR 2001 YH 2011 GM 27 2010 VK 201 2013 FZ 27 2014 UM 33 1999 CD 158 Cubewanos : IAU : Makemake Additional objects proposed by Brown and Tancredi : 2002 MS Salacia Quaoar Varuna Varda 2004 GV 2002 AW 2002 TX 2005 RR 2003 OP 2005 RN Possibly : Chaos Altjira Sila - Nunam 2002 UX 2007 JJ 2005 UQ 2004 TY 2003 QW 1998 SN 2002 KX Praamzius 2004 NT 2010 FX 86 2002 CY 248 2010 VR 11 Rhadamanthus Scattered disc IAU : Eris Additional objects proposed by Brown and Tancredi : 2007 OR 1996 TL 2001 UR 2005 RM Possibly : 2002 TC 2004 XA 2005 QU 2006 QH 181 2007 UK 2010 EK 139 2010 KZ 39 2010 RE 64 2010 RF 43 2010 TJ 2013 FY 27 2008 OG 19 1996 GQ 2012 HH 1999 CC 2010 VZ 98 Area uncertain Captured satellites that were once dwarf planets : Triton ( captured by Neptune ) Phoebe ( captured by Saturn, and no longer rounded ) Possibly : 2011 FW 62 ( lost ) 2000 YW V774104 Detached objects Possibly : 2004 XR 190 2010 GB 174 2008 ST 291 1995 TL 2005 TB 2003 QX 113 2003 FY 2004 VN 112 2000 CR Sednoids Objects proposed by Brown and Tancredi : Sedna Possibly : 2012 VP 113 See also : Charon Vanth Dysnomia Hiʻiaka Mesoplanet Planemo List of trans - Neptunian objects List of possible dwarf planets List of Solar System objects List of Solar System objects by size The Solar System The Sun Mercury Venus Earth Mars Ceres Jupiter Saturn Uranus Neptune Pluto Haumea Makemake Eris Planets Terrestrial planets Mercury Venus Earth Mars Giant planets Jupiter Saturn Uranus Neptune Dwarf planets Ceres Pluto Haumea Makemake Eris Rings Jovian Saturnian ( Rhean ) Charikloan Chironean Uranian Neptunian Haumean Moons 1 Terrestrial ( Moon ) Other near - Earth objects 2 Martian Phobos Deimos 69 Jovian Ganymede Callisto Io Europa all 62 Saturnian Titan Rhea Iapetus Dione Tethys Enceladus Mimas Hyperion Phoebe all 27 Uranian Titania Oberon Umbriel Ariel Miranda all 14 Neptunian Triton Proteus Nereid all 5 Plutonian Charon Nix Hydra Kerberos Styx 2 Haumean Hiʻiaka Namaka 1 Makemakean ( S / 2015 ( 136472 ) 1 ) 1 Eridian ( Dysnomia ) Lists Solar System objects By size By discovery date Minor planets Gravitationally rounded objects Possible dwarf planets Natural satellites Comets Small Solar System bodies Meteoroids Minor planets moons Comets Damocloids Mercury - crossers Venus - crossers Venus trojans Near - Earth objects Earth - crossers Earth trojans Mars - crossers Mars trojans Asteroid belt Asteroids first discovered : Ceres Pallas Juno Vesta Families Notable asteroids Kirkwood gap Main - belt comets Jupiter trojans Jupiter - crossers Centaurs Saturn - crossers Uranus trojans Uranus - crossers Neptune trojans Cis - Neptunian objects Trans - Neptunian objects Neptune - crossers Plutoids Kuiper belt Plutinos Cubewanos Scattered disc Detached objects Sednoids Hills cloud Oort cloud Hypothetical objects Vulcan Vulcanoids Phaeton Planet V Theia Fifth giant Planets beyond Neptune Tyche Nemesis Planet Nine Exploration ( outline ) Discovery Astronomy Timeline Spaceflight Robotic spacecraft Human spaceflight Colonization List of probes Timeline Mercury Venus Moon Mars Ceres Asteroids Mining Comets Jupiter Saturn Uranus Neptune Pluto Deep space Outline of the Solar System Portals Solar System Astronomy Earth sciences Mars Jupiter Uranus Cosmology Solar System → Local Interstellar Cloud → Local Bubble → Gould Belt → Orion Arm → Milky Way → Milky Way subgroup → Local Group → Virgo Supercluster → Laniakea Supercluster → Pisces -- Cetus Supercluster Complex → Observable universe → Universe Each arrow ( → ) may be read as `` within '' or `` part of ''. LCCN : sh85022130 GND : 1085654478 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Eris_(dwarf_planet)&oldid=807756155 '' Categories : Eris ( dwarf planet ) Astronomical objects discovered in 2005 Discoveries by Michael E. Brown Pluto 's planethood Scattered disc and detached objects Minor planets named from Greek mythology Named minor planets Numbered minor planets Discoveries by Chad Trujillo Discoveries by David L. 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Question: what is the significance of the celestial object eris
Answer: most massive and second-largest dwarf planet known in the Solar System