A three-dimensional model of 1862 Apollo based on its light curve.
|Discovered by||Karl Reinmuth|
|Discovery site||Heidelberg-Königstuhl State Observatory|
|Discovery date||24 April 1932|
|Orbital characteristics |
|Epoch 16 October 2009 (JD 2455120.5)|
|Uncertainty parameter 0|
|Observation arc||84.25 yr|
|1.78 yr (651.12 d)|
Average orbital speed
|Dimensions||1.5 km (mean diameter)|
|0.12 d (3.065 h)|
|Temperature||~ 222 K|
It is the namesake of the Apollo asteroids, and the first one discovered, although because it was lost for a time its asteroid number (1862) is higher than that of some other Apollo asteroids such as 1566 Icarus. Analysis of the spin of this object provided observational evidence of the YORP effect.
On November 4, 2005, it was announced that an asteroid moon, or satellite of Apollo, had been detected by radar observations from Arecibo Observatory, Puerto Rico, October 29 – November 2, 2005. The standard provisional designation for this satellite is S/2005 (1862) 1. The announcement is contained in the International Astronomical Union Circular (IAUC) 8627 . The satellite is just 80 m across and orbits Apollo closely, in an orbit a mere 3 km in radius .
Potentially hazardous object
1862 Apollo is a potentially hazardous asteroid (PHA) because its minimum orbit intersection distance (MOID) is less than 0.05 AU and its diameter is greater than 150 meters. The Earth MOID is 0.0258 AU (3,860,000 km; 2,400,000 mi). The orbit is well determined for the next several hundred years. On 17 May 2075 it will pass 0.0083 AU (1,240,000 km; 770,000 mi) from Venus.
- Durech, J.; Vokrouhlický, D.; Kaasalainen, M.; Weissman, P.; Lowry, S. C.; Beshore, E.; Higgins, D.; Krugly, Y. N.; et al. (September 2008). "New photometric observations of asteroids (1862) Apollo and (25143) Itokawa – an analysis of YORP effect" (PDF). Astronomy and Astrophysics 488 (1): 345–350. Bibcode:2008A&A...488..345D. doi:10.1051/0004-6361:200809663.
- "JPL Small-Body Database Browser: 1862 Apollo (1932 HA)" (2015-03-16 last obs.). Jet Propulsion Laboratory. Retrieved September 2015.
- Gehrels, Tom (1994). Hazards Due to Comets and Asteroids. Tucson: University of Arizona Press. pp. 540–543. ISBN 0816515050.