|Discovery site||Lincoln Lab ETS|
|Discovery date||24 April 2008|
|MPC designation||2008 HJ|
|NEO · Apollo |
|Orbital characteristics |
|Epoch 13 January 2016 (JD 2457400.5)|
|Uncertainty parameter 6|
|Aphelion||2.29553 AU (343.406 Gm) (Q)|
|Perihelion||0.968318 AU (144.8583 Gm) (q)|
|1.63192 AU (244.132 Gm) (a)|
|2.08 yr (761.46 d)|
|0° 28m 21.99s /day (n)|
|Earth MOID||0.00170917 AU (255,688 km)|
|Jupiter MOID||2.75111 AU (411.560 Gm)|
|Mass||5×106 kg (assumed)|
Sidereal rotation period
|42.7 s (0.01185 h)|
It was discovered by Lincoln Laboratory ETS, New Mexico. Observers M. Bezpalko, D. Torres, R. Kracke, G. Spitz, J. Kistler. Richard Miles using the Faulkes Telescope South at Siding Spring Observatory, Australia determined that the asteroid rotates rapidly. It measures only 12 m by 24 m and is very dense, having a mass of about 5,000 tonnes. If the asteroid were not dense, it is probable that the rapid rotation would cause the asteroid to disrupt and fly apart.
- "JPL Small-Body Database Browser: (2008 HJ)" (last observation: 2008-04-30; arc: 6 days; uncertainty: 6). Jet Propulsion Laboratory. Retrieved 30 March 2016.
- Record spin for new-found asteroid, BBC.com, 30 May 2008
- "Earth Impact Risk Summary: 2008 HJ". NASA/JPL Near-Earth Object Program Office. Retrieved 22 January 2018.