Discovery date November 27, 1864 Aphelion 3.3701 AU Semi-major axis 2.7655 AU Orbits Sun Discoverer Robert Luther | Minor planet category Main belt Perihelion 2.1609 AU Discovered 27 November 1864 Spectral type S-type asteroid Named after Alcmene | |
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Discovered by Karl Theodor Robert Luther Discovery site Düsseldorf-Bilk Observatory Robert Luther discoveries 47 Aglaja, 95 Arethusa, 68 Leto, 26 Proserpina | ||
82 Alkmene (/ælkˈmiːniː/ alk-MEE-nee) is a main-belt asteroid. Alkmene was discovered by R. Luther on November 27, 1864, and named after Alcmene, the mother of Herakles in Greek mythology. Based on IRAS data, Alkmene is estimated to be about 61 kilometres (38 mi) in diameter. A satellite has been suggested based on 1985 lightcurve data.
Asteroid Alkmene occulted the apparent magnitude 7.5 star HIP 99229 in the constellation of Capricornus on 18 September 2014 around 06:41 UT (17 September 23:41 PDT) and was centered on Sacramento, CA. Alkmene projected an eclipse shadow that moves at about 2 miles (3.2 km) per second. Asteroid occultations allow for accurate 2-dimensional mapping of an asteroids silhouette when observed by multiple telescopes separated by about 10 km (6.2 mi).