82 Alkmene
A three-dimensional model of 82 Alkmene based on its light curve. | |
Discovery | |
---|---|
Discovered by | Karl Theodor Robert Luther |
Discovery date | November 27, 1864 |
Designations | |
Named after | Alcmene |
Main belt | |
Orbital characteristics | |
Epoch 2014-Dec-09 (JD 2457000.5) | |
Aphelion | 3.3701 AU |
Perihelion | 2.1609 AU |
2.7655 AU | |
Eccentricity | 0.2186 |
4.60 yr | |
Average orbital speed | 17.70 km/s |
192.56° | |
Inclination | 2.8286° |
25.507° | |
111.27° | |
Physical characteristics | |
Dimensions | 61 ± 1.5 km (IRAS)[1] |
Mass | 2.4×1017 kg (assumed) |
Mean density | ? g/cm³ |
0.0170 m/s² (assumed) | |
0.0322 km/s (assumed) | |
12.999 h[1] | |
Albedo | 0.208[1] |
Temperature | ~168 K |
Spectral type | S[1] |
8.40[1] | |
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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.[1] A satellite has been suggested based on 1985 lightcurve data.[2]
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.[3][4] 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).