1862 Apollo
Template:Short description Template:Use dmy dates Template:Infobox planet
1862 Apollo Template:IPAc-en is a stony asteroid, approximately 1.5 kilometers in diameter, classified as a near-Earth object (NEO). It was discovered by German astronomer Karl Reinmuth at Heidelberg Observatory on 24 April 1932, but was lost and not recovered until 1973.
It is the namesake and the first recognized member of the Apollo asteroids, a subgroup of NEOs which are Earth-crossers, that is, they cross the orbit of the Earth when viewed perpendicularly to the ecliptic plane (crossing an orbit is a more general term than actually intersecting it). In addition, since Apollo's orbit is highly eccentric, it crosses the orbits of Venus and Mars and is therefore called a Venus-crosser and Mars-crosser as well.
Although Apollo was the first Apollo asteroid to be discovered, its official IAU-number (1862) is higher than that of some other Apollo asteroids such as 1566 Icarus, because it was a lost asteroid for more than 40 years and other bodies were numbered in the meantime. The analysis of its rotation provided observational evidence of the YORP effect.<ref name="yorp"/>
It is named after the Greek god Apollo. He is the god of the Sun, child of Zeus and Leto, after which the minor planets 5731 Zeus and 68 Leto are named.<ref name="springer" />
Satellite
On 4 November 2005, it was announced that an asteroid moon, or satellite of Apollo, had been detected by radar observations from Arecibo Observatory, Puerto Rico, on 19 October – 2 November 2005. The announcement is contained in the International Astronomical Union Circular (IAUC) 8627.<ref>Template:Cite web</ref> The satellite is only Template:Convert across and orbits Apollo just Template:Convert away from the asteroid itself.<ref name="archive">Template:Cite web</ref> From the surface of Apollo, the satellite would have an angular diameter of about 2.0835 degrees.<ref group="lower-alpha">Calculated from the formula <math>\delta</math> = (206265) d / D arcseconds. (see Angular diameter)</ref>
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. Apollo's Earth MOID is Template:Convert.<ref name=jpldata /> Its orbit is well-determined for the next several hundred years. On 17 May 2075 it will pass Template:Convert from Venus.<ref name=jpldata />
See also
Notes
References
External links
- Lightcurve plot of 1862 Apollo, Palmer Divide Observatory, B. D. Warner (2005)
- Asteroids with Satellites, Robert Johnston, johnstonsarchive.net
- Asteroid Lightcurve Database (LCDB), query form (info Template:Webarchive)
- Dictionary of Minor Planet Names, Google books
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- Template:NeoDys
- Template:ESA-SSA
- Template:JPL small body
Template:Minor planets navigator Template:Small Solar System bodies Template:Authority control