1999 OJ4

Discovery and designation Orbit of 1999 OJ4 Mauna Kea Observatory July 18, 1999 38.9821849 AU (5,831.6519 Gm) 36.9289344 AU (5,524.4900 Gm) 37.9555596 AU (5,678.0709 Gm) .027048087 233.84 years 275.664317° 4.00407256° 127.534875° 296.645795° 1 1.5395 deg / yr 233.84216 yr (85410.848 d) 75 km (47 mi) 0.21 (geometric)[1][4] 43 K (-230°C) 7.1[2]

1999 OJ4 is a fairly small cubewano that orbits in a nearly circular orbit. It is orbited by S/2005 (1999 OJ4) 1, a moon just 3 kilometres smaller than 1999 OJ4 itself.[1]

Orbit and Relationship with the Kuiper Belt

1999 OJ4 orbit characterizes it as a classical Kuiper Belt object, or cubewano. Due to its nearly circular orbit and low inclination, it is also in the "cold" population of cubewanos. As a result, it is likely reddish in color.[5][6]

Moon

1999 OJ4 has one moon, S/2005 (1999 OJ4) 1. This moon was discovered by the Hubble Space Telescope[4] on October 5, 2013.[1] It orbits 3,267 kilometres away from 1999 OJ4, completing one orbit every 84.115 days.[1][4] At 72 km, it is nearly the same size as 1999 OJ4. From the surface of 1999 OJ4, S/2005 (1999 OJ4) 1 would have an apparent diameter of roughly 8.11°,[a] over fourteen times the apparent size of the Sun from Earth.

Notes

1. ^ Calculated by solving $\scriptstyle{\mathrm{tan}\left(\frac{\theta}{2}\right) = \frac{\mathrm{radius~of~moon}}{\mathrm{distance~from~surface~of~asteroid~to~center~of~moon}}}$.

References

1. Johnston, W. R. (28 December 2008). "1999 OJ4". Johnston's Archive. Retrieved 2013-10-14.
2. ^ a b
3. ^ "1999 OJ4". Lowell. 26 March 2013. Retrieved 2013-10-14.
4. ^ a b c Grundy, W. M. et al. (2009). "Mutual Orbits and Masses of Six Transneptunian Binaries". Icarus. arXiv:0812.3126. Bibcode:2009Icar..200..627G. doi:10.1016/j.icarus.2008.12.008.
5. ^ A. Doressoundiram, N. Peixinho, C. de Bergh, S. Fornasier, P. Thebault, M. A. Barucci,C. Veillet (October 2002). "The Color Distribution in the Edgeworth-Kuiper Belt". The Astronomical Journal 124 (4): 2279. arXiv:astro-ph/0206468. Bibcode:2002AJ....124.2279D. doi:10.1086/342447.
6. ^ Nuno Peixinho, Pedro Lacerda and David Jewitt (August 2008). "Color-inclination relation of the classical Kuiper belt objects". The Astronomical Journal 136 (5): 1837. arXiv:0808.3025. Bibcode:2008AJ....136.1837P. doi:10.1088/0004-6256/136/5/1837.