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1862 Apollo

1862 Apollo
A model of 1862 Apollo viewed from the pole (top) and from the equator (bottom). The irregular shape of asteroids like 1862 Apollo means that photons adsorbed and re-emitted from the surface can produce a net torque that gradually makes the asteroids spin faster – what is known to astronomers as the "YORP" effect. Image credit: Mikko Kaasalainen and Josef Durech
1862 Apollo is the prototype asteroid of the Apollo group. It was discovered by the German astronomer Karl Reinmuth (1892–1979) in 1932, when it approached Earth to within 10.5 million km (0.07 AU), but was then lost until 1973. Apollo can come as close to Earth as 4.2 million km (0.028 AU) and also make near passes of Venus and Mars, whose orbits it crosses at perihelion and aphelion, respectively.

diameter 1.4 km
spectral class Q
rotational period 3.063 hours
semimajor axis 1.486 AU
perihelion 0.65 AU
aphelion 2.30 AU
eccentricity 0.57
inclination 6.4°
period 622 days

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