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1998 WW31
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Number
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-
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Provisional name
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1998 WW31
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Class
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Cubewano
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Discovery date
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18.11.1998, 05:09:44 UT, Kitt Peak, AZ, USA
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Discovery chart
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Discovery position
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22° Taurus 54' Rx
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Time of announcement
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28.01.1999 - 22:30 UT
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Orbital period
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296.7 years
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Orbit
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Aphelion
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48.521 AU
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Perihelion
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40.541 AU
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Semimajor axis
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44.531 AU
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Magnitude
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6.1
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Diameter
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115 - 356 km
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Inclination
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6.8
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 1998 WW31 has a binary companion. This is the first trans-Neptunian binary discovered since Pluto. It is the most symmetrical of the known binary systems. The two objects are very close in size. The orbit is highly eccentric and the orbital period is long, very different from the Pluto-Charon system. The mutual eclipses are estimated to happen about 50 years from now, possibly in 2055 or in 2056 (with a few years uncertainty). |
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Satellite
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S/2000 (1998 WW31) 1
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Discovery
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image was taken 22.12.2000, Canada-France-Hawaii Telescope (CFHT), Mauna Kea, Hawaii, USA,
the object was found from the image in April 2001 |
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Time of announcement
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16.04.2001 IAU circular 7610
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Distance between pair
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22,300 km +/- 800 km
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Orbital period
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574 +/- 10 d
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