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PUT THAT COOKIE DOWN! --[[User:?Dr. Questionmark?|?Dr. Questionmark?]] ([[User talk:?Dr. Questionmark?|talk]]) 22:31, 6 May 2009 (UTC) |
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{{Infobox Planet |
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| bgcolour = #FFFFC0 |
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| name = Haumea |
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| image = [[File:2003 EL61.jpg|300px]] |
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| caption = [[Keck telescope|Keck]] image of Haumea and its two moons. [[Hi'iaka (moon)|Hi{{okina}}iaka]] is above Haumea (centre), and [[Namaka (moon)|Namaka]] is directly below. |
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| discovery = yes |
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| discoverer= [[Michael E. Brown|Brown]] ''et al.''; [[José Luis Ortiz Moreno|Ortiz]] ''et al.'' (neither official) |
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| discovered=2004 December 28 (Brown ''et al.''); 2005 July (Ortiz ''et al.'') |
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| mp_name= (136108) Haumea |
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| alt_names={{mp|2003 EL|61}} |
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| mp_category=[[dwarf planet]], [[plutoid]], [[Trans-Neptunian object|TNO]] <span style="white-space:nowrap;">(delisted [[cubewano]])</span><ref name="K09A63" /><ref name="Buie"> |
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{{cite web |
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|author=[[Marc W. Buie]] |
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|date=2008-06-25 |
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|title=Orbit Fit and Astrometric record for 136108 |
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|publisher=Southwest Research Institute (Space Science Department) |
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|url=http://www.boulder.swri.edu/~buie/kbo/astrom/136108.html |
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|accessdate=2008-10-02}}</ref><br />fifth-order [[Resonant trans-Neptunian object|12:7 resonance]]<ref name="candidate" /> |
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| orbit_ref = <ref name="jpldata" /> |
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| epoch=2008-11-30 ([[Julian day|JD]] 2454800.5) |
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| semimajor=6,452 [[Giga|G]][[metre|m]]<br>43.132 [[Astronomical unit|AU]] |
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| perihelion=5,194 Gm<br>34.721 AU |
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| aphelion=7,710 Gm<br>51.544 AU |
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| eccentricity=0.195 01 |
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| period=103 468 [[day|d]] (283.28 [[Julian year (astronomy)|yr]]) |
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| inclination=28.22[[degree (angle)|°]] |
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| asc_node=121.10° |
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| arg_peri=239.18° |
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| mean_anomaly=202.67° |
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| avg_speed=4.484 km/[[second|s]] |
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| satellites=2 |
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| physical_characteristics=yes |
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| dimensions= ≈1,960 × 1,518 × 996 km ([[Keck telescope|Keck]])<ref name="Rabinowitz2005" /><br />([[geometric mean|≈1,436 km]])<br />1,150 {{±|250|100}} km ([[Spitzer Space Telescope|Spitzer]])<ref name="spitzer"> |
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{{cite web |
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|title=Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope |
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|author=John Stansberry, Will Grundy, Mike Brown, Dale Cruikshank, John Spencer, David Trilling, Jean-Luc Margot |
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|work=University of Arizona, Lowell Observatory, California Institute of Technology, NASA Ames Research Center, Southwest Research Institute, Cornell University |
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|url=http://arxiv.org/abs/astro-ph/0702538v2 |
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|date=2007-02-20 |
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|accessdate=2008-07-27}}</ref> |
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| radius=≈980 × 759 × 498 km (≈750 km) |
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| surface_area=≈2{{e|7}} [[kilometer square|km<sup>2</sup>]] |
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| volume= |
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| mass=(4.006 ± 0.040){{e|21}} [[kilogram|kg]]<ref name="Ragozzine&Brown2009"> |
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{{cite journal |
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|last=Ragozzine |
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|first=D. |
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|coauthors=Brown, M.E. |
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|date=2009 |
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|title=Orbits and Masses of the Satellites of the Dwarf Planet Haumea = 2003 EL61 |
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|journal=The Astronomical Journal |
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|url=http://arxiv.org/abs/0903.4213}} |
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</ref> |
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| density=2.6–3.3 g/[[cubic centimetre|cm³]]<ref name="Rabinowitz2005"/> |
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| surface_grav=0.44 m/s² |
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| escape_velocity=0.84 km/s |
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| sidereal_day=0.163 146 ± 0.000 004 d<br />(3.915 5 ± 0.000 1 h)<ref name="hour"> |
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{{cite journal |
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|title=High-Precision Photometry of Extreme KBO 2003 EL61 |
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|author=Pedro Lacerda, David Jewitt and Nuno Peixinho |
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|date=2008-04-02 |journal=The Astronomical Journal |
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|volume= 135 |pages=1749–1756 |
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|url=http://www.iop.org/EJ/abstract/1538-3881/135/5/1749 |
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|accessdate=2008-09-22 |doi=10.1088/0004-6256/135/5/1749}}</ref> |
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| spectral_type=? |
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| magnitude = 17.3 ([[Opposition (astronomy and astrology)|opposition]])<ref name=AstDys>{{cite web |
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|title=AstDys (136108) Haumea Ephemerides |
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|publisher=Department of Mathematics, University of Pisa, Italy |
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|url=http://hamilton.dm.unipi.it/astdys/index.php?pc=1.1.3.0&n=Haumea |
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|accessdate=2009-03-19}}</ref><ref name="Horizons"> |
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{{cite web |
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|title=HORIZONS Web-Interface |
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|publisher=[http://ssd.jpl.nasa.gov NASA Jet Propulsion Laboratory Solar System Dynamics] |
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|url=http://ssd.jpl.nasa.gov/horizons.cgi?find_body=1&body_group=sb&sstr=2003EL61 |
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|accessdate=2008-07-02}}</ref> |
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| abs_magnitude=0.17<ref name="jpldata"> |
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{{cite web |
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|date=2008-05-10 last obs |
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|title=Jet Propulsion Laboratory Small-Body Database Browser: 136108 Haumea (({{mp|2003 EL|61}}) |
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|publisher=NASA's Jet Propulsion Laboratory |
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|url=http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=136108 |
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|accessdate=2008-06-11}}</ref> |
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| albedo=0.7 ± 0.1<ref name="Rabinowitz2005"/><br>0.84 {{±|0.1|0.2}}<ref name="spitzer"/> |
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| single_temperature=<50 [[kelvin|K]]<ref name="Trujillo 2006"/> |
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}} |
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'''Haumea''' ({{pron-en|haʊˈmeɪə}} or {{IPAlink-en|ˌhɑː.uːˈmeɪə}}),<ref group=note>In US dictionary transcription, {{USdict|how·mā′·ə}} or {{USdict|hâ′·ōō·mā′·ə}}: Three syllables according to [http://www.wcpo.com/news/local/story/New-Dwarf-Planet-Named-For-Hawaiian-Goddess/r7yMFg_UeUSqz7xt-JHt8w.cspx ''New Dwarf Planet Named For Hawaiian Goddess''] (WCPO, 20-9-2008) and the English pronunciation in Hawaii; four syllables according to Brown's students.[http://dps08.astro.cornell.edu/AAS_WebcastSchedule_2008.html][http://365daysofastronomy.org/2009/03/31/march-31st/ podcast: Dwarf Planet Haumea (Darin Ragozzine)]</ref> [[Minor planet names|formal designation]] '''(136108) Haumea''', is a [[dwarf planet]] in the [[Kuiper belt]]. Its mass is one-third the mass of [[Pluto]].<ref group=note>Haumea is 1400 times less massive than Earth (0.07% the mass of Earth).</ref> It was discovered in 2004 by a team headed by [[Michael E. Brown|Mike Brown]] of [[Caltech]] at the [[Palomar Observatory]]<!--Keck was used for follow-up imaging, and discovered the moons and the surface of ice--> in the United States, and in 2005 by a team headed by [[José Luis Ortiz Moreno|J. L. Ortiz]] at the [[Sierra Nevada Observatory]] in Spain, though the latter claim has been contested. On September 17, 2008, it was accepted as a dwarf planet by the [[International Astronomical Union]] (IAU) and named after [[Haumea (mythology)|Haumea]], the Hawaiian goddess of childbirth. |
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Haumea's extreme elongation makes it unique among known [[trans-Neptunian object]]s (TNOs). Although its shape has not been directly observed, calculations from its [[light curve]] suggest it is an [[ellipsoid]], with its greatest [[Axis of rotation|axis]] twice as long as its shortest. Nonetheless, its [[gravity]] is believed sufficient for it to have relaxed into [[hydrostatic equilibrium]], thereby meeting the definition of a dwarf planet. This elongation, along with its unusually rapid rotation, high density, and high [[albedo]] (from a surface of crystalline water ice), are thought to be the results of a [[Impact event|giant collision]], which left Haumea the largest member of a [[collisional family]] that includes several large TNOs and its two known moons. |
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==Classification== |
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[[File:Haumea.GIF|200px|thumb|left|The nominal [[libration]] of Haumea in a [[rotating frame]]. (See [[2_Pallas#Characteristics|2 Pallas]] for an example of non-librating.)]] |
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Haumea is a [[plutoid]],<ref name="usgs" /> a [[technical term|term]] used to describe [[dwarf planet]]s beyond Neptune's orbit. Its status as a [[dwarf planet]] means it is presumed to be massive enough to have been rounded by its own gravity, but not to have [[clearing the neighbourhood|cleared its neighbourhood]] of similar objects. Although Haumea appears to be far from an [[oblate spheroid]], its [[ellipsoid]]al [[shape]] is thought to result from its rapid [[rotation]] (in much the same way that a [[water balloon]] stretches out when tossed with a spin), and not from a lack of sufficient gravity to overcome the [[tensile strength]] of its [[material]].<ref name="iau" /> Haumea was initially listed as a [[classical Kuiper belt object]] (classical KBO) in 2006 by the [[Minor Planet Center]], but it is no longer listed as such.<ref name="K09A63"> {{cite web |
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|title=Minor Planet Electronic Circular 2009-A63 : Distant Minor Planets (2009 JAN. 29.0 TT) |
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|date=2009-01-13|publisher=Minor Planet Center |
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|url=http://www.cfa.harvard.edu/mpec/K09/K09A63.html |
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|accessdate=2009-02-03 |
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|format=[http://cfa-www.harvard.edu/iau/mpec/K06/K06X45.html 2006 provisional Cubewano listing]}}</ref> The nominal trajectory suggests that it is in a fifth-order [[Resonant trans-Neptunian object|12:7 resonance with Neptune]]<ref group=note name=resonance/> since the [[Apsis|perihelion]] distance of 35 AU is near the [[Perturbation (astronomy)|limit of stability]] with Neptune.<ref name="candidate" /> Further observations of the orbit will be required to verify its dynamical status. |
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==Name== |
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Until it was given a permanent name, the Caltech discovery team used the nickname "[[Santa Claus|Santa]]" among themselves, as they had discovered Haumea on December 28, 2004, just after [[Christmas]].<ref> |
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{{cite web |
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|title=Santa et al. |
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|date=2005-09-10 |
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|publisher= NASA Astrobiology Magazine |
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|url=http://www.astrobio.net/news/modules.php?op=modload&name=News&file=article&sid=1707&mode=thread&order=0&thold=0 |
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|accessdate=2008-10-16}} |
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</ref> The Spanish team proposed a separate discovery to the [[Minor Planet Center]] (MPC) in July 2005. On July 29, 2005, Haumea was given its first official label, the temporary designation {{mp|2003 EL|61}}, with the "2003" based on the date of the Spanish discovery image. On September 7, 2006, it was numbered and admitted into the official minor planet catalogue as {{mp|(136108) 2003 EL|61}}. |
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Following [[Astronomical naming conventions#Minor planets|guidelines]] established by the IAU that classical KBOs be given names of mythological beings associated with creation,<ref> |
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{{cite news |
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|title=Naming of astronomical objects: Minor planets |
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|work=International Astronomical Union |
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|url=http://www.iau.org/public_press/themes/naming/#minorplanets |
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|accessdate=2008-11-17}} |
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</ref> in September 2006 the Caltech team submitted formal names from [[Hawaiian mythology]] to the IAU for both {{mp|(136108) 2003 EL|61}} and its moons, in order "to pay homage to the place where the satellites were discovered".<ref name="mike"> |
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{{cite web |
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|title=Dwarf planets: Haumea |
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|author=Mike Brown |
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|work=CalTech |
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|date=2008-09-17 |
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|url=http://web.gps.caltech.edu/~mbrown/2003EL61/ |
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|accessdate=2008-09-18}} |
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</ref> The names were proposed by [[David L. Rabinowitz|David Rabinowitz]] of the Caltech team.<ref name="iau"> |
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{{cite news |
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| url=http://www.iau.org/public_press/news/release/iau0807/ |
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| title=IAU names fifth dwarf planet Haumea |
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| publisher=IAU Press Release |
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| date=2008-09-17 |
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| accessdate = 2008-09-17}} |
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</ref> Haumea is the matron goddess of the island of [[Hawaii (island)|Hawai{{okina}}i]], where the [[Mauna Kea Observatory]] is located. In addition, she is identified with [[Papahanaumoku|Pāpā]], the goddess of the earth and wife of [[Wākea]] (space),<ref name="craig"> |
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{{cite book |
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|author=Robert D. Craig |
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|title=Handbook of Polynesian Mythology |
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|publisher=ABC-CLIO |
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|year=2004 |
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|url=http://books.google.ca/books?id=LOZuirJWXvUC&pg=PA128&dq=haumea&lr=&sig=ACfU3U3pDIRAYQihFLO5R-rkQ1Y2G3OHxg |
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|page=128 }} |
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</ref> which is appropriate because {{mp|2003 EL|61}} is thought to be composed almost entirely of solid rock, without the thick ice mantle over a small rocky core typical of other known Kuiper belt objects.<ref name="iaunews"> |
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{{cite web |
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|title=News Release - IAU0807: IAU names fifth dwarf planet Haumea |
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|work=International Astronomical Union |
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|date=2008-09-17 |
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|url=http://www.iau.org/public_press/news/release/iau0807/ |
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|accessdate=2008-09-18}} |
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</ref><ref name="BrownBarkume2007"/> Lastly, Haumea is the goddess of fertility and childbirth, with many children who sprang from different parts of her body;<ref name="craig" /> this corresponds to the swarm of icy bodies thought to have broken off the dwarf planet during an ancient collision.<ref name="BrownBarkume2007"/> The two known moons, also believed to have been born in this manner,<ref name="BrownBarkume2007"/> are thus named after two of Haumea's daughters, [[Hi'iaka|Hi{{okina}}iaka]] and [[Nāmaka]].<ref name="iaunews" /> |
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==Discovery controversy== |
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{{main|Controversy over the discovery of Haumea}} |
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Two teams claim credit for the discovery of Haumea. Mike Brown and his team at Caltech discovered Haumea in December 2004 on images they had taken on May 6, 2004. On July 20, 2005, they published an online abstract of a report intended to announce the discovery at a conference in September 2005.<ref name="trail"> |
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{{cite web |
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|author=Michael E Brown |
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|url=http://www.gps.caltech.edu/~mbrown/planetlila/ortiz/ |
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|title=The electronic trail of the discovery of {{mp|2003 EL|61}} |
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|work=CalTech |
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|accessdate=2006-08-16}} |
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</ref> At around this time, José Luis Ortiz Moreno and his team at the Instituto de Astrofísica de Andalucía at Sierra Nevada Observatory in Spain found Haumea on images taken on March 7–10, 2003.<ref name="Sanz" /> Ortiz emailed the Minor Planet Center with their discovery on the night of July 27, 2005, giving a discovery date of March 7, 2003.<ref name="Sanz" /> |
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Brown came to suspect the Spanish team of fraud upon learning that his observation logs were accessed from the Spanish observatory the day before the discovery announcement. These logs included enough information to allow the Ortiz team to [[precovery|precover]] Haumea in their 2003 images, and they were accessed again just before Ortiz scheduled telescope time to obtain confirmation images for a second announcement to the MPC on July 29. Ortiz later admitted he had accessed the Caltech observation logs but denied any wrongdoing, stating he was merely verifying whether they had discovered a new object.<ref name="ortiz1"> |
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{{cite news |
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| author=Jeff Hecht |
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| url=http://www.newscientist.com/article/dn8033 |
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| title=Astronomer denies improper use of web data |
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| date=2005-09-21 |
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| publisher=NewScientist.com |
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| accessdate=2009-01-12}}</ref> |
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IAU protocol is that discovery credit for a [[minor planet]] goes to whoever first submits a report to the MPC with enough positional data for a decent determination of its orbit, and that the credited discoverer has priority in choosing a name. However, the IAU announcement on September 17, 2008, that Haumea had been accepted as a dwarf planet, made no mention of a discoverer. The location of discovery was listed as the Sierra Nevada Observatory of the Spanish team,<ref name="usgs" /><ref name="marsden"> |
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{{cite web |
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|title=Controversial dwarf planet finally named 'Haumea' |
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|author=Rachel Courtland |
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|work=NewScientistSpace |
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|date=2008-09-19 |
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|url=http://space.newscientist.com/article/dn14759-controversial-dwarf-planet-finally-named-haumea.html |
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|accessdate=2008-09-19}} |
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</ref> but the chosen name, Haumea, was the Caltech proposal.<ref name="Sanz"> |
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{{cite web |
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|title=La historia de Ataecina vs Haumea |
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|url=http://www.infoastro.com/200809/26ataecina-haumea.html |
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|publisher=infoastro.com |
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|author= Pablo Santos Sanz |
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|date=2008-09-26 |
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|accessdate=2008-09-29 |
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|language=Spanish}}</ref> |
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==Orbit== |
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[[File:TheKuiperBelt Orbits 2003EL61.svg|thumb|300px|Orbits of Haumea (yellow) and [[Pluto]] (red), relative to that of [[Neptune]] (grey), {{as of|2006|04|lc=on}}]] |
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Haumea has a typical orbit for a classical Kuiper belt object, with an [[orbital period]] of 283 Earth years, a [[perihelion]] of 35 [[Astronomical Units|AU]], and an [[orbital inclination]] of 28°.<ref name="jpldata" /> It passed [[aphelion]] in early 1992,<ref name="Horizons" /> and is currently more than 50 AU from the Sun.<ref name=AstDys/> |
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Haumea's orbit has a slightly greater [[orbital eccentricity|eccentricity]] than the other members of [[Haumea family|its collisional family]]. This is thought to be due to Haumea's weak fifth-order<ref group=note name=resonance>In principle, the strength of a resonance is inversely proportional to the difference between the numerator and denominator, which is called its 'order'. The lower the difference (order), the stronger the resonance will be. A 12:7 resonance is fifth order (12 − 7 = 5), which is fairly weak.</ref> 12:7 orbital resonance with Neptune gradually modifying its initial orbit, over the course of a billion years,<ref name="BrownBarkume2007"/><ref name="largest"> |
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{{cite web |
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|title=The largest Kuiper belt objects |
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|author=Michael E. Brown |
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|work=CalTech |
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|url=http://www.gps.caltech.edu/~mbrown/papers/ps/kbochap.pdf |
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|format=PDF|accessdate=2008-09-19}} |
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</ref> through the [[Kozai mechanism|Kozai effect]], which allows the exchange of an orbit's inclination for increased eccentricity.<ref name="BrownBarkume2007"/><ref name="Nesvorny2001"> |
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{{cite journal |
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|last=Nesvorný |
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|first=D |
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|coauthors=Roig, F. |
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|date=2001 |
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|title=Mean Motion Resonances in the Transneptunian Region Part II: The 1 : 2, 3 : 4, and Weaker Resonances |
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|journal=Icarus |
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|volume=150 |
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|issue=1 |
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|pages=104-123 |
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|url=http://adsabs.harvard.edu/abs/2001Icar..150..104N}} |
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</ref><ref name="Kuchner2002"> |
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{{cite journal |
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|last=Kuchner |
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|first=Marc J. |
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|coauthors=Brown, Michael E.; Holman, Matthew |
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|date=2002 |
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|title=Long-Term Dynamics and the Orbital Inclinations of the Classical Kuiper Belt Objects |
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|journal=The Astronomical Journal |
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|volume=124 |
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|issue=2 |
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|pages=1221-1230 |
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|url=http://adsabs.harvard.edu/abs/2002AJ....124.1221K}} |
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</ref> |
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With a [[visual magnitude]] of 17.3,<ref name=AstDys/> Haumea is the [[List of the brightest KBOs|third brightest object]] in the Kuiper belt after Pluto and {{dp|Makemake}}, and easily observable with a large amateur telescope.<ref name="Rabinowitz2005"/> However, since the planets and most [[small Solar System bodies]] share a [[invariable plane|common orbital alignment]] from their [[formation and evolution of the Solar System|formation]] in the [[protoplanetary disk|primordial disk]] of the Solar System, most early surveys for distant objects focused on the projection on the sky of this common plane, called the [[ecliptic]].<ref name="TrujilloBrown2003"> |
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{{cite journal |
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|author=C. A. Trujillo and M. E. Brown |
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|title=The Caltech Wide Area Sky Survey. Earth Moon and Planets |
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|pages=92–99 |volume=112 |month=June | year=2003 |
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|doi=10.1023/B:MOON.0000031929.19729.a1 |
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|journal=Earth Moon and Planets}} |
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</ref> As the region of sky close to the ecliptic became well explored, later sky surveys began looking for objects that had been dynamically excited into orbits with higher inclinations, as well as more distant objects, with slower [[mean motion]]s across the sky.<ref name="Brown2004"> |
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{{cite journal |
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|author=M. E. Brown, C. Trujillo, D. L. Rabinowitz |
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|year=2004 |
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|title=Discovery of a candidate inner Oort cloud planetoid |
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|journal=The Astrophysical Journal |
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|volume=617 |issue=1 |pages=645–649 |
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|doi=10.1086/422095}} |
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</ref><ref name="Schwamb2008"> |
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{{cite journal |
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|author=M. E. Schwamb, M. E. Brown, D. L. Rabinowitz |
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|year=2008 |
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|title=Constraints on the distant population in the region of Sedna |
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|journal=American Astronomical Society |
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|issue=DPS meeting \#40}, \#38.07}} |
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</ref> These surveys eventually covered the location of Haumea, with its high orbital inclination and current position far from the ecliptic. |
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==Physical characteristics== |
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<imagemap> |
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Image:EightTNOs.png|thumb|250px|right|Haumea compared to [[Eris (dwarf planet)|Eris]], [[Pluto]], [[Makemake (dwarf planet)|Makemake]], [[90377 Sedna|Sedna]], [[Orcus]], [[Quaoar]], [[20000 Varuna|Varuna]], and [[Earth]] (all to scale) |
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#Earth |
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rect 646 1714 2142 1994 [[Earth|The Earth]] |
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#Eris and Dysnomia |
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circle 226 412 16 [[Dysnomia (moon)|Dysnomia]] |
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circle 350 626 197 [[Eris (dwarf planet)|(136199) Eris]] |
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#Pluto and Charon |
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circle 1252 684 86 [[Charon (moon)|Charon]] |
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circle 1038 632 188 [[Pluto|(134340) Pluto]] |
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#Makemake |
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circle 1786 614 142 [[Makemake (dwarf planet)|(136472) Makemake]] |
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#Haumea |
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circle 2438 616 155 [[Haumea (dwarf planet)|(136108) Haumea]] |
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#Sedna |
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circle 342 1305 137 [[90377 Sedna|(90377) Sedna]] |
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#Orcus |
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circle 1088 1305 114 [[90482 Orcus|(90482) Orcus]] |
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#Quaoar |
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circle 1784 1305 97 [[50000 Quaoar|(50000) Quaoar]] |
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#Varuna |
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circle 2420 1305 58 [[20000 Varuna|(20000) Varuna]] |
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#link to image (under all other links) |
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rect 0 0 2749 1994 [[File:EightTNOs.png]] |
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desc none |
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# - setting this to "bottom-right" will display a (rather large) icon linking to the graphic, if desired |
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#Notes: |
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#Details on the new coding for clickable images is here: [[mw:Extension:ImageMap]] |
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#While it may look strange, it's important to keep the codes for a particular system in order. The clickable coding treats the first object created in an area as the one on top. |
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#Moons should be placed on "top" so that their smaller circles won't disappear "under" their respective primaries. |
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</imagemap> |
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Since Haumea has moons, the mass of the system can be calculated from their orbits using [[Kepler's laws of planetary motion#Kepler's understanding of the laws|Kepler's third law]]. The result is {{nowrap|4.2{{e|21}} kg,}} 28% the mass of the Plutonian system and 6% the mass of the Earth's [[Moon]]. Nearly all of this mass is in Haumea.<ref name="Brown2005"> |
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{{cite journal |
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|author=[[Michael E. Brown|M. E. Brown]], A. H. Bouchez, [[David L. Rabinowitz|D. L. Rabinowitz]], R. Sari, [[Chadwick A. Trujillo|C. A. Trujillo]], M. A. van Dam, R. Campbell, J. Chin, S. Hartman, E. Johansson, R. Lafon, D. LeMignant, P. Stomski, D. Summers, P. L. Wizinowich |
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|title=Keck Observatory laser guide star adaptive optics discovery and characterization of a satellite to large Kuiper belt object {{mp|2003 EL|61}} |
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|journal=The Astrophysical Journal Letters |
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|volume=632 |pages=L45 |date=October 2005 |
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|format=[http://www.gps.caltech.edu/%7Embrown/papers/ps/EL61.pdf full text from Caltech] |
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|doi=10.1086/497641}}</ref> |
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Haumea displays large fluctuations in brightness over a period of four hours, which can only be explained by a rotational period of this length. This is faster than any other known equilibrium body in the [[Solar System]], and indeed faster than any other known body larger than 100 km in diameter.<ref name="Rabinowitz2005"/> This rapid rotation is thought to have been caused by the impact that created its satellites and collisional family.<ref name="BrownBarkume2007"/> |
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===Size, shape, and composition=== |
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The size of a Solar System object can be derived from its [[optical magnitude]], its distance, and its [[albedo]]. Objects appear bright to Earth observers either because they are large or because they are highly reflective. If their reflectivity (albedo) can be ascertained, then a rough estimate can be made of their size. For most distant objects, the albedo is unknown, but Haumea is large and bright enough for its [[Infrared|thermal emission]] to be measured, which has given an approximate value for its albedo and thus its size.<ref name="spitzer" /> However, the calculation of its dimensions is complicated by its rapid rotation. The [[Rigid body dynamics|rotational physics]] of [[deformable bodies]] predicts that over as little as a hundred days,<ref name="Rabinowitz2005"/> a body rotating as rapidly as Haumea will have been distorted into the [[Hydrostatic equilibrium|equilibrium form]] of a [[ellipsoid#Rotational equilibrium|scalene ellipsoid]]. It is thought that most of the fluctuation in Haumea's brightness is caused not by local differences in albedo but by the alternation of the side view and end view as seen from Earth.<ref name="Rabinowitz2005"/> |
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[[File:Haumea.svg|thumb|left|The calculated ellipsoid shape of Haumea, 1,960×1,518×996 km (assuming an [[albedo]] of 0.73). At left are the minimum and maximum equatorial silhouettes (1,960×996 and 1,518×996 km); at right is the view from the [[geographical pole|pole]] (1,960×1,518 km).]] |
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The rotation and amplitude of Haumea's [[Light curve#Planetology|light curve]] place strong constraints on its composition. If Haumea had a low [[density]] like Pluto, with a thick mantle of [[volatiles|ice]] over a small [[silicate|rocky]] core, its rapid rotation would have elongated it to a greater extent than the fluctuations in its brightness allow. Such considerations constrain its density to a range of 2.6–3.3 g/cm³.<ref name="Rabinowitz2005"/><ref group=note> By comparison, Earth's rocky moon has a density of 3.3 g/cm³, while Pluto, which is typical of icy objects in the Kuiper belt, has a density of 2.0 g/cm³.</ref> This range covers the values for [[silicate minerals]] such as [[olivine]] and [[pyroxene]], which make up much of the [[Planetary differentiation|rocky objects]] in the Solar System. This suggests that the bulk of Haumea is rock covered with a relatively thin layer of ice. A thick ice mantle more typical of Kuiper belt objects may have been blasted off during the impact that formed the Haumean collisional family.<ref name="BrownBarkume2007"/> |
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The denser the object in hydrostatic equilibrium, the more spherical it must be for a given rotational period, placing constraints on Haumea's possible dimensions. Fitting its accurately known mass, its rotation, and its inferred density to an equilibrium ellipsoid predicts that Haumea is approximately the diameter of Pluto along its longest axis and about half that at its poles. Since no observations of [[asteroid occultation|occultations]] of stars by Haumea or occultations of the dwarf planet with its moons have yet been made, direct, precise measurements of its dimensions, like those that have [[Solar eclipses on Pluto|been made for Pluto]], do not yet exist. |
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Several ellipsoid-model calculations of Haumea's dimensions have been made. The first model produced after Haumea's discovery was calculated from [[Observatory#Ground-based observatories|ground-based]] observations of Haumea's [[light curve]] at [[visible spectrum|optical]] wavelengths: it provided a total length of 1,960 to 2,500 km and a [[visible spectrum|visual]] [[Albedo#Astronomical_albedo|albedo]] (p<sub>v</sub>) greater than 0.6.<ref name="Rabinowitz2005"> |
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{{cite journal |
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|author=[[David L. Rabinowitz|D. L. Rabinowitz]], K. M. Barkume, [[Michael E. Brown|M. E. Brown]], H. G. Roe, M. Schwartz, S. W. Tourtellotte, [[Chadwick A. Trujillo|C. A. Trujillo]] |
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|year=2006 |
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|title=Photometric Observations Constraining the Size, Shape, and Albedo of {{mp|2003 EL|61}}, a Rapidly Rotating, Pluto-Sized Object in the Kuiper Belt |
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|journal=The Astrophysical Journal |
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|volume=639|issue=2|pages=1238–1251 |
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|format=[http://arxiv.org/abs/astro-ph/0509401 preprint on arXiv]|doi=10.1086/499575}} |
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</ref> |
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This model gives approximate triaxial dimensions of 2,000 x 1,500 x 1,000 km, with an albedo of 0.73.<ref name="Rabinowitz2005"/> |
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The [[Spitzer Space Telescope]] has estimated Haumea to have a diameter of 1,150 {{±|250|100}} km and an albedo of 0.84 {{±|0.1|0.2}}, from [[Photometry (astronomy)|photometry]] at [[infrared]] wavelengths of 70 μm.<ref name="spitzer"/> |
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Subsequent light curve analyses have suggested an equivalent circular diameter of 1,450 km.<ref name="Lacerda2007"> |
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{{cite journal |
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|last=Lacerda |
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|first=Pedro |
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|coauthors=Jewitt, David C. |
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|date=2007 |
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|title=Densities of Solar System Objects from Their Rotational Light Curves |
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|journal=The Astronomical Journal |
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|volume=133 |
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|issue=4 |
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|pages=1393 |
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|url=http://adsabs.harvard.edu/abs/2007AJ....133.1393L}} |
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</ref> |
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These independent size estimates overlap at an average [[geometric mean]] diameter of roughly 1,400 km. This makes Haumea one of the largest trans-Neptunian objects discovered, third or fourth after {{dp|Eris}}, {{dp|Pluto}}, and perhaps {{dp|Makemake}}, and larger than {{dp|Sedna}}, {{dp|Orcus}}, or {{dp|Quaoar}}.<ref> |
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{{cite journal |
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| author = J. Stansberry, W. Grundy, M. Brown, ''et al.'' |
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| title=Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope |
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|url=http://arxiv.org/abs/astro-ph/0702538v1 |
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| journal = The Solar System beyond Neptune |
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| publisher = University of Arizona Press |
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| date=2008-04-17 |
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| format=abstract |
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| accessdate=2008-08-04}} |
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</ref> |
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===Surface=== |
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In addition to the large fluctuations in Haumea's light curve due to the body's shape, which affect all [[Colour index|colours]] equally, smaller independent colour variations seen in both visible and near-infrared wavelengths show a region on the surface that differs both in colour and in albedo.<ref name="hour"/><ref name="Lacerda2009"> |
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{{cite journal |
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|last=Lacerda |
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|first=Pedro |
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|date=2009 |
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|title=Time-Resolved Near-Infrared Photometry of Extreme Kuiper Belt Object Haumea |
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|journal=The Astronomical Journal |
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|volume=137 |
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|issue=2 |
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|pages=3404-3413 |
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|url=http://adsabs.harvard.edu/abs/2009AJ....137.3404L}} |
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</ref> |
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Thus Haumea may have a mottled surface reminiscent of Pluto, if not as extreme. |
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In 2005, the [[Gemini Observatory|Gemini]] and [[Keck Observatory|Keck]] telescopes obtained [[spectrum|spectra]] of Haumea which showed strong crystalline [[ice|water ice]] features similar to the surface of Pluto's moon [[Charon (moon)|Charon]].<ref name="Trujillo 2006"> |
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{{cite journal |
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|author=[[Chadwick A. Trujillo]], [[Michael E. Brown]], Kristina Barkume, Emily Shaller, [[David L. Rabinowitz]] |
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|title=The Surface of {{mp|2003 EL|61}} in the Near Infrared |
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|journal=The Astrophysical Journal |
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|volume=655|date=February 2007|pages=1172–1178 |
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|format=[http://arxiv.org/abs/astro-ph/0601618 preprint] |
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|doi=10.1086/509861}} |
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</ref> This is peculiar, because crystalline ice forms at temperatures above 110 K, while the surface temperature of Haumea is below 50 K, a temperature at which [[amorphous]] ice is formed.<ref name="Trujillo 2006"/> In addition, the structure of crystalline ice is unstable under the constant rain of [[cosmic ray]]s and energetic particles from the Sun that strike trans-Neptunian objects.<ref name="Trujillo 2006"/> The timescale for the crystalline ice to revert to [[amorphous ice]] under this bombardment is on the order of ten million years,<ref> |
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{{cite web |
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|title=Charon: An ice machine in the ultimate deep freeze |
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|work=Gemini Observatory |
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|date=2007-07-17 |
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|url=http://www.spaceflightnow.com/news/n0707/17charon/ |
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|accessdate=2007-07-18}} |
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</ref> while trans-Neptunian objects have been in their present cold-temperature locations for timescales of thousands of millions of years.<ref name="largest" /> Radiation damage should also redden and darken the surface of trans-Neptunian objects where the common surface materials of [[organic molecule|organic]] ices and [[tholin|tholin-like]] compounds are present, as is the case with Pluto. Therefore, the spectra and [[colour index|colour]] suggest Haumea and its family members have undergone recent resurfacing that produced fresh ice. However, no plausible resurfacing mechanism has been suggested.<ref> |
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{{cite journal |
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|title=The Youthful Appearance of the 2003 EL61 Collisional Family |
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|author=David L. Rabinowitz, Bradley E. Schaefer, Martha W. Schaefer, Suzanne W. Tourtellotte |
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|date=2008-04-17 |
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|journal=ArXiv.org |
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|url=http://arxiv.org/abs/0804.2864 |
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|accessdate=2008-09-20}}</ref> |
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Haumea is as bright as snow, with an albedo in the range of 0.6–0.8, consistent with crystalline ice.<ref name="Rabinowitz2005"/> Other large TNOs such as {{dp|Eris}} appear to have albedos as high or higher.<ref> |
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{{cite journal |
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| title = Direct measurement of the size of 2003 UB313 from the [[Hubble Space Telescope]] |
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| author = [[Michael E. Brown|M. E. Brown]], E.L. Schaller, H.G. Roe, [[David L. Rabinowitz|D. L. Rabinowitz]], [[Chadwick A. Trujillo|C. A. Trujillo]] |
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| journal = The Astronomical Journal |
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| date = 2006-02-08| volume =643| issue = 2| pages = L61–L63 |
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| doi = 10.1086/504843 |
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| url=http://www.gps.caltech.edu/~mbrown/papers/ps/xsize.pdf|format=PDF}} |
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</ref> Best-fit modeling of the surface spectra suggested that 66% to 80% of the Haumean surface appears to be pure crystalline water ice, with one contributor to the high albedo possibly [[hydrogen cyanide]] or [[Silicate minerals#Phyllosilicates|phyllosilicate clays]].<ref name="Trujillo 2006"/> Inorganic cyanide salts such as copper potassium cyanide may also be present.<ref name="Trujillo 2006"/> |
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However, further studies of the visible and near infrared spectra suggest a homomorphous surface covered by an intimate 1:1 mixture of amorphous and crystalline ice, together with no more than 8% organics. The absence of ammonia hydrate excludes cryovolcanism and the observations confirm that the collisional event must have happened more than 100 million years ago, in agreement with the dynamic studies.<ref> |
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{{cite journal |
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| title = Study of the Surface of 2003 EL61, the largest carbon-depleted object in the trans-neptunian belt |
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| author = N. Pinilla-Alonso, R. Brunetto, J. Licandro, R. Gil-Hutton, T. L. Roush, and G. Strazzulla |
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| journal = Astronomy and Astrophysics |
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| date = March 2009| volume =496 | issue = 2 |
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| url=http://arxiv.org/abs/0803.1080 |format=PDF}} |
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</ref> |
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The absence of measurable [[methane]] in the spectra of Haumea is consistent with a warm [[Impact crater|collisional history]] that would have removed such [[volatiles]]<ref name="Trujillo 2006"/>, |
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in contrast to {{dp|Makemake}}.<ref name="Tegler07"> |
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{{citeweb |
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|author=S.C. Tegler, W. Grundy, W. Romanishin, G. Consolmagno, K. Mogren, F. Vilas |
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|title=Optical Spectroscopy of the Large Kuiper Belt Objects 136472 ({{mp|2005 FY|9}}) and 136108 ({{mp|2003 EL|61}}) |
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|url=http://arXiv.org/abs/astro-ph/0611135 |
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|accessdate=2008-10-19}} |
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</ref> |
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==Moons== |
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{{main|Moons of Haumea|Hiʻiaka (moon)|Namaka (moon)}} |
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[[File:2003EL61art.jpg|thumb|200px|Artist's conception of Haumea with its moons [[Hi'iaka (moon)|Hi{{okina}}iaka]] and [[Namaka (moon)|Namaka]]. The moons are actually much more distant than depicted here.]]Two small [[natural satellite|satellites]] have been discovered orbiting Haumea, [[Hi'iaka (moon)|(136108) Haumea I Hi{{okina}}iaka]] and [[Namaka (moon)|(136108) Haumea II Namaka]].<ref name="usgs"> |
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{{cite news |
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| publisher=US Geological Survey Gazetteer of Planetary Nomenclature |
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| title=Dwarf Planets and their Systems |
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| url=http://planetarynames.wr.usgs.gov/append7.html#DwarfPlanets |
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| accessdate=2008-09-17}} |
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</ref> Brown's team discovered both in 2005, through observations of Haumea using the [[W.M. Keck Observatory]]. |
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Hi{{okina}}iaka, at first nicknamed "[[Rudolph the Red-Nosed Reindeer|Rudolph]]" by the Caltech team,<ref> |
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{{cite web |
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|author=Kenneth Chang |
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|title=Piecing Together the Clues of an Old Collision, Iceball by Iceball |
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|url=http://www.nytimes.com/2007/03/20/science/space/20kuip.html |
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|work=[[New York Times]] |
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|date=2007-03-20 |
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|accessdate=2008-10-12 }} |
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</ref> was discovered January 26, 2005.<ref> |
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{{cite journal |
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|author= [[Michael E. Brown|M. E. Brown]], A. H. Bouchez, D. Rabinowitz. R. Sari, C. A. Trujillo, M. van Dam, R. Campbell, J. Chin, S. Hardman, E. Johansson, R. Lafon, D. Le Mignant, P. Stomski, D. Summers, and P. Wizinowich |
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|title=Keck Observatory Laser Guide Star Adaptive Optics Discovery and Characterization of a Satellite to the Large Kuiper Belt Object {{mp|2003 EL|61}} |
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|journal=The Astrophysical Journal Letters |
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|volume=632|date=2005-09-02|pages=L45–L48 |
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|url=http://www.journals.uchicago.edu/doi/pdf/10.1086/497641|doi=10.1086/497641}} |
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</ref> It is the outer and, at roughly 310 km in diameter, the larger and brighter of the two, and orbits Haumea in a nearly circular path every 49 days.<ref name="blitzen"> |
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{{cite journal |
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|title=Satellites of the largest Kuiper belt objects |
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|author=M. E. Brown, M. A. van Dam, A. H. Bouchez et al. |
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|date=2005-10-02 |
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|journal=The Astrophysical Journal |
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|volume=639|pages=43–46 |
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|url=http://web.gps.caltech.edu/~mbrown/papers/ps/gab.pdf |
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|format=PDF|accessdate=2009-09-29 |
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|doi=10.1086/501524}} |
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</ref> Strong absorption features at 1.5 and 2 [[micrometre]]s in the [[infrared]] spectrum are consistent with nearly pure crystalline water ice covering much of the surface.<ref name="Barkume2006"> |
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{{cite journal |
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|author=K. M Barkume, [[Michael E. Brown|M. E. Brown]], and E. L. Schaller|title=Water Ice on the Satellite of Kuiper Belt Object {{mp|2003 EL|61}} |
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|journal=The Astrophysical Journal |
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|volume=640|date=March 2006|pages=L87–L89 |
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|url=http://arxiv.org/abs/astro-ph/0601534 preprint |
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|doi=10.1086/503159}} |
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</ref> The unusual spectrum, along with similar absorption lines on Haumea, led Brown and colleagues to conclude that capture was an unlikely model for the system's formation, and that the Haumean moons must be fragments of Haumea itself.<ref name="largest" /> |
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Namaka, the smaller, inner satellite of Haumea, was discovered on June 30, 2005, and nicknamed "[[Blitzen the Reindeer|Blitzen]]". It is a tenth the mass of Hi{{okina}}iaka, orbits Haumea in 18 days in a highly elliptical, [[Osculating orbit|non-Keplerian]] orbit, and as of 2008 is inclined 13° from the larger moon, which [[Perturbation (astronomy)|perturbs]] its orbit.<ref name="RagozzineDPS08" /> |
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The relatively large eccentricities together with the mutual inclination of the orbits of the satellites are unexpected as they should have been damped by the [[tidal acceleration|tidal effects]]. A relatively recent passage by a (3:1) resonance might explain the current excited orbits of the Haumea moons.<ref name="Brown2009"> |
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D. Ragozzine, [[Michael E. Brown|M. E. Brown]] ''Orbits And Masses Of The Satellites Of The Dwarf Planet Haumea = 2003 EL61'', To appear in The Astronomical Journal (2009) [http://arxiv.org/abs/0903.4213 Preprint on arXiv]</ref> |
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At present, the orbits of the Haumean moons appear almost exactly edge-on from Earth, with Namaka periodically [[occultation|occulting]] Haumea.<ref name="IAU8949">{{cite web |
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|url=http://www.cfa.harvard.edu/~fabrycky/EL61/ |
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|title=IAU Circular 8949 |
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|date=2008-09-17 |
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|publisher=International Astronomical Union |
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|accessdate=2008-12-06}} |
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</ref> Observation of such transits would provide precise information on the size and shape of Haumea and its moons,<ref name="events09"/> as happened in [[Solar eclipses on Pluto|the late 1980s with Pluto and Charon.]]<ref> |
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{{cite web |
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|author=Lucy-Ann Adams McFadden, Paul Robert Weissman, Torrence V. Johnson |
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|title=Encyclopedia of the Solar System |
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|url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA545&lpg=PA545&dq=mutual+event+pluto&source=web&ots=jDOfb3sWHL&sig=jjLkVTF21FuL-8TiGUT0gy7X5nQ&hl=en |
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|accessdate=2008-10-17}} |
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</ref> The tiny change in brightness of the system during these occultations will require at least a [[Optical telescope#Optical Research telescopes|medium]]-[[aperture]] [[List of optical telescopes|professional telescope]] for detection.<ref name="events09"/><ref name="FabryckyDPS08"> |
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{{cite web |
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|author=D. C. Fabrycky, M. J. Holman, D. Ragozzine, M. E. Brown, T. A. Lister, D. M. Terndrup, J. Djordjevic, E. F. Young, L. A. Young, R. R. Howell |
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|title=Mutual Events of 2003 EL61 and its Inner Satellite |
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|url=http://www.abstractsonline.com/viewer/viewAbstract.asp?CKey={DC1A2D7A-1E8E-4C58-A2AB-F0FA8673515C}&MKey={35A8F7D5-A145-4C52-8514-0B0340308E94}&AKey={AAF9AABA-B0FF-4235-8AEC-74F22FC76386}&SKey={545CAD5F-068B-4FFC-A6E2-1F2A0C6ED978} |
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|work=AAS DPS conference 2008 |
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|accessdate=2008-10-17}} |
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</ref> Hi{{okina}}iaka last occulted Haumea in 1999, a few years before discovery, and will not do so again for some 130 years.<ref name="shadows"> |
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{{cite web |
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|title=Moon shadow Monday (fixed) |
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|author=Mike Brown |
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|date=2008-05-18 |
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|publisher=Mike Brown's Planets |
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|url=http://www.mikebrownsplanets.com/2008/05/moon-shadow-monday-fixed.html |
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|accessdate=2008-09-27}} |
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</ref> However, in a situation unique among [[regular moon|regular satellites]], Namaka's orbit is being greatly [[Precession (astronomy)#Anomalistic precession|torqued]] by Hi{{okina}}iaka, preserving the viewing angle of Namaka–Haumea transits for several more years.<ref name="RagozzineDPS08"> |
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{{cite web |
|||
|author=D. Ragozzine, M. E. Brown, C. A. Trujillo, E. L. Schaller |
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|title=Orbits and Masses of the 2003 EL61 Satellite System |
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|url=http://www.abstractsonline.com/viewer/viewAbstract.asp?CKey={421E1C09-F75A-4ED0-916C-8C0DDB81754D}&MKey={35A8F7D5-A145-4C52-8514-0B0340308E94}&AKey={AAF9AABA-B0FF-4235-8AEC-74F22FC76386}&SKey={545CAD5F-068B-4FFC-A6E2-1F2A0C6ED978} |
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|work=AAS DPS conference 2008 |
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|accessdate=2008-10-17}} |
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</ref><ref name="events09"> |
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{{cite web |
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|url=http://web.gps.caltech.edu/~mbrown/2003EL61/mutual/ |
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|title=Mutual events of Haumea and Namaka |
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|accessdate=2009-02-18}} |
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</ref><ref name="FabryckyDPS08" /> |
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== Collisional family == |
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{{main|Haumea family}} |
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Haumea is the largest member of its [[collisional family]], a group of astronomical objects with similar physical and orbital characteristics thought to have formed when a larger progenitor was shattered by an impact.<ref name="BrownBarkume2007"> |
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{{cite journal |
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|author=Michael E. Brown, Kristina M. Barkume; Darin Ragozzine; Emily L. Schaller |
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|date=2007-01-19 |
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|title=A collisional family of icy objects in the Kuiper belt |
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|journal=Nature |
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|volume=446 |issue=7133 |pages=294–296 |
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|doi=10.1038/nature05619 |
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|accessdate=2008-09-27}} |
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</ref> This family is the first to be identified among TNOs and includes—beside Haumea and its moons—{{mpl|(55636) 2002 TX|300}} (≈600 km), {{mpl|(24835) 1995 SM|55}} (< 700 km), {{mpl|(19308) 1996 TO|66}} (≈500 km), {{mpl|(120178) 2003 OP|32}} (< 700 km), and {{mpl|(145453) 2005 RR|43}} (< 700 km).<ref name="candidate" /> |
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The presence of the collisional family could imply that Haumea and its "offspring" might have originated in the [[scattered disc]]. In today's sparsely populated Kuiper belt, the chance of such a collision occurring over the age of the Solar System is less than 0.1 percent.<ref name="disc" /> The family could not have formed in the denser primordial Kuiper belt because such a close-knit group would have been disrupted by [[Neptune#Formation and migration|Neptune's migration]] into the belt—the believed cause of the belt's current low density.<ref name="disc" /> Therefore it appears likely that the dynamic scattered disc region, in which the possibility of such a collision is far higher, is the place of origin for the object that generated Haumea and its kin.<ref name="disc"> |
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{{cite journal |
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|title=On a Scattered Disc Origin for the {{mp|2003 EL|61}} Collisional Family—an Example of the Importance of Collisions in the Dynamics of Small Bodies |
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|author=Harold F. Levison, Alessandro Morbidelli, David Vokrouhlický and William F. Bottke |
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|date=2008-04-14 |
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|journal= The Astronomical Journal |
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|volume= 136|pages= 1079–1088 |
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|doi= 10.1088/0004-6256/136/3/1079|url=http://www.iop.org/EJ/abstract/1538-3881/136/3/1079 |
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|accessdate=2008-09-19}}</ref> |
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Because it would have taken at least a billion years for the group to have diffused as far as it has, the collision which created the Haumea family is believed to have occurred very early in the Solar System's history.<ref name="candidate"> |
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{{cite journal |
|||
|title=Candidate Members and Age Estimate of the Family of Kuiper Belt Object {{mp|2003 EL|61}} |
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|author=D. Ragozzine; M. E. Brown |
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|journal=The Astronomical Journal |
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|volume=134|issue=6|pages= 2160–2167 |
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|date=2007-09-04 |
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|url=http://adsabs.harvard.edu/abs/2007arXiv0709.0328R |
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|accessdate=2008-09-19 |
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|doi=10.1086/522334}}</ref> |
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==Notes== |
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<references group=note/> |
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==References== |
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{{Reflist|2}} |
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==External links== |
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* [http://neo.jpl.nasa.gov/orbits/2003el61.html Visualization of Haumea's orbit] by NASA |
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* [http://www.johnstonsarchive.net/astro/astmoons/am-136108.html (136108) Haumea, Hiʻiaka, and Namaka] at Johnston's Archive.com (updated September 17, 2008) |
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* [[International Year of Astronomy|International Year of Astronomy 2009]] [http://365daysofastronomy.org/2009/03/31/march-31st/ podcast: Dwarf Planet Haumea (Darin Ragozzine)] |
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{{Solar System}} |
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{{Haumea}} |
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{{Moons of dwarf planets}} |
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{{MinorPlanets Navigator|(136107) 2003 EY58|(136109) 2003 FA22|PageName=(136108) Haumea|state=autocollapse}} |
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{{Trans-Neptunian objects}} |
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{{Trans-Neptunian dwarf planets}} |
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{{featured article}} |
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[[Category:Haumea| ]] |
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{{Link FA|cs}} |
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[[bn:হাউমেইয়া (বামন গ্রহ)]] |
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[[be:2003 EL61 (аб'ект поясу Койпера)]] |
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[[ca:Haumea]] |
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[[cs:Haumea (plutoid)]] |
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[[da:Haumea (dværgplanet)]] |
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[[de:Haumea (Zwergplanet)]] |
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[[eo:Haŭmeo]] |
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[[et:Haumea (kääbusplaneet)]] |
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[[el:Χαουμέια (πλανήτης νάνος)]] |
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[[es:Haumea (planeta enano)]] |
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[[fa:هائومیا (سیاره کوتوله)]] |
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[[fr:(136108) Haumea]] |
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[[gu:હૌમેયા (વામન ગ્રહ)]] |
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[[ko:하우메아]] |
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[[id:Haumea (planet katai)]] |
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[[it:Haumea (astronomia)]] |
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[[he:האומיה (כוכב לכת ננסי)]] |
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[[ka:ჰაუმეა]] |
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[[la:Haumea (planetula)]] |
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[[lv:Haumeja]] |
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[[lt:Haumea]] |
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[[hu:Haumea]] |
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[[mr:हौमिआ (बटु ग्रह)]] |
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[[nl:Haumea]] |
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[[ja:ハウメア (準惑星)]] |
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[[no:Haumea]] |
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[[nn:136108 Haumea]] |
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[[nds:Haumea (Dwargplanet)]] |
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[[pl:136108 Haumea]] |
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[[pt:Haumea]] |
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[[ro:Haumea (planetă pitică)]] |
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[[ru:Хаумеа (карликовая планета)]] |
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[[simple:Haumea (dwarf planet)]] |
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[[sk:136108 Haumea]] |
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[[sl:Haumea]] |
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[[sr:Хаумеа (патуљаста планета)]] |
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[[fi:Haumea]] |
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[[sv:Haumea (dvärgplanet)]] |
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[[tl:Haumea (duwendeng planeta)]] |
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[[th:เฮาเมอา]] |
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[[tr:Haumea (cüce gezegen)]] |
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[[uk:Хаумеа (карликова планета)]] |
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[[vi:Haumea (hành tinh lùn)]] |
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[[zh:妊神星]] |
Revision as of 22:31, 6 May 2009
PUT THAT COOKIE DOWN! --?Dr. Questionmark? (talk) 22:31, 6 May 2009 (UTC)