|Discovery site||Kitt Peak National Obs.|
|Discovery date||8 April 2008|
|(457175) 2008 GO98|
|2008 GO98 · 362P|
|main-belt · (outer)|
|Epoch 4 December 2015 (JD 2457360.5)|
|Uncertainty parameter 0|
|Observation arc||16.05 yr (5,862 d)|
|7.89 yr (2,883 d)|
|0° 7m 29.64s / day|
|Jupiter MOID||0.3592 AU|
|5.5–24.7 km (est.)|
14.64 h (calculated)
(457175) 2008 GO98, provisional designation 2008 GO98 with cometary number 362P, is a Hildian asteroid and rare main-belt comet from the outermost regions of the asteroid belt, approximately 15 kilometers (9 miles) in diameter. It was discovered on 8 April 2008, by astronomers of the Spacewatch program at Kitt Peak National Observatory near Tucson, Arizona, in the United States. The presumably carbonaceous body has a rotation period of 10.7 hours.
2008 GO98 is classified as a member of the dynamical Hilda group, as well as a main-belt comet that shows clear cometary activity, which has also been described as a "quasi Hilda comet". Orbital backward integration suggests that it might have been a centaur or trans-Neptunian object that ended its dynamical evolution as a quasi Hilda comet.
It orbits the Sun in the outer asteroid belt at a distance of 2.9–5.1 AU once every 7 years and 11 months (2,883 days; semi-major axis of 3.96 AU). Its orbit has an eccentricity of 0.28 and an inclination of 16° with respect to the ecliptic. The body's observation arc begins with a precovery taken by the Sloan Digital Sky Survey in October 2001, more than 5 years prior to its official discovery observation by Spacewatch.
2008 GO98 has a Jupiter Tisserand's parameter (TJ) of 2.926, just below Jewitt's threshold of 3, which serves as a distinction between the main-belt asteroids (TJ larger than 3) and the Jupiter-family comets (TJ between 2 and 3).
This minor planet was numbered by the Minor Planet Center on 16 February 2016 (M.P.C. 98587). As of 2020, it has not been named.
2008 GO98 is an assumed C-type asteroid.
In August 2017, a rotational lightcurve of 2008 GO98 was obtained from photometric observations by American astronomer Brian Warner at the Palmer Divide Station (U82) in California. Lightcurve analysis gave a rotation period of 10.74±0.01 hours with a small brightness amplitude of 0.12 magnitude (U=2).[a]
The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous body of 0.057 and calculates a diameter of 14.64 kilometers based on an absolute magnitude of 12.9. Other estimates, taking into account several published magnitude measurements and a large range of albedo assumptions, estimate a diameter range of 5.5 to 24.7 kilometers.