Discovered by K. Reinmuth Discovery date 24 April 1932 Discovered 24 April 1932 Asteroid group Apollo asteroid | Discovery site Heidelberg Obs. Alternative names 1932 HA Orbits Sun Discoverer Karl Wilhelm Reinmuth Moon S/2005 (1862) 1 | |
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Named after Apollo(Greek mythology) Minor planet category NEO · PHAVenus-crosserMars-crosserApollo Similar Karl Wilhelm Reinmuth discoveries, Other celestial objects | ||
1862 Apollo /əˈpɒloʊ/ 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 lost and not recovered until 1973.
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It is the namesake and the first recognized member of the Apollo asteroids, a subgroup of NEOs which are Earth-crosser, that is they cross the orbit of Earth when view perpendicular to the ecliptic plane (crossing an orbit is a more general term that 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, due to the fact that 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.
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.
Moon
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 only 80 m (260 ft) across and orbits Apollo just 3 km (1.9 mi) away from the asteroid itself. From the surface of Apollo, S/2005 (1862) 1 would have an angular diameter of about 2.0835 degrees.
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 0.0257 AU (3,840,000 km; 2,390,000 mi). Its 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.