| Discovery date 1 April 2005 Minor planet category Aten NEO,PHA Discovered 1 April 2005 Discovery site Siding Spring Observatory Discoverer Siding Spring Survey | MPC designation (308242) 2005 GO21 Observation arc 3385 days (9.27 yr) Absolute magnitude 16.5 Asteroid group Aten asteroid | |
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| Discovered by Siding Spring Survey (E12)0.5-m Uppsala Schmidt Aphelion 1.0093 AU (150.99 Gm) (Q) Similar 4581 Asclepius, 2012 DR30, 4179 Toutatis | ||
(308242) 2005 GO21 is a large Aten near-Earth asteroid and potentially hazardous object. It has a well determined orbit with an observation arc of 7 years and an uncertainty parameter of 0. It was discovered on 1 April 2005 by the Siding Spring Survey at an apparent magnitude of 18.1 using the 0.5-metre (20 in) Uppsala Southern Schmidt Telescope.
Based on an absolute magnitude of 16.4, the asteroid has an estimated diameter of 1.6 km (within a factor of two). (308242) 2005 GO21 is the largest potentially hazardous asteroid (PHA) discovered in 2005. On 21 June 2012 it passed Earth at a distance of 0.043963 AU (6,576,800 km; 4,086,600 mi). The 2012 passage was studied with radar using Goldstone and Arecibo.
References
(308242) 2005 GO21 Wikipedia(Text) CC BY-SA