86 Semele

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86 Semele
Discovery
Discovered by Friedrich Tietjen
Discovery date January 4, 1866
Designations
Alternative names  
Minor planet
category
Main belt
Epoch December 31, 2006 (JD 2454100.5)
Aphelion 562.652 Gm (3.761 AU)
Perihelion 369.116 Gm (2.467 AU)
Semi-major axis 465.884 Gm (3.114 AU)
Eccentricity 0.208
Orbital period 2007.366 d (5.50 a)
Average orbital speed 16.69 km/s
Mean anomaly 264.875°
Inclination 4.822°
Longitude of ascending node 86.452°
Argument of perihelion 307.886°
Physical characteristics
Dimensions 120.6 km
Mass 1.8×1018 kg
Mean density ? g/cm³
Equatorial surface gravity 0.0337 m/s²
Escape velocity 0.0638 km/s
Rotation period ? d
Albedo 0.047 [1]
Temperature ~158 K
Spectral type C
Absolute magnitude 8.54

86 Semele (sem'-i-lee, IPA: /ˈsɛmɨli/) is a large and very dark main belt asteroid. It is probably composed of carbonates. Semele was discovered by German astronomer Friedrich Tietjen on January 4, 1866. It was his first and only asteroid discovery. It is named after Semele, the mother of Dionysus in Greek mythology.

[edit] References

  1. ^ Asteroid Data Sets