120 Lachesis

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120 Lachesis
Discovery
Discovered by Alphonse Borrelly
Discovery date April 10, 1872
Designations
Alternative names  
Minor planet
category
Main belt
Epoch December 31, 2006 (JD 2454100.5)
Aphelion 493.828 Gm (3.301 AU)
Perihelion 438.480 Gm (2.931 AU)
Semi-major axis 466.154 Gm (3.116 AU)
Eccentricity 0.059
Orbital period 2009.115 d (5.50 a)
Average orbital speed 16.86 km/s
Mean anomaly 150.174°
Inclination 6.954°
Longitude of ascending node 341.511°
Argument of perihelion 232.006°
Physical characteristics
Dimensions 174.1 km
Mass 5.5×1018 kg
Mean density ? g/cm³
Equatorial surface gravity 0.0487 m/s²
Escape velocity 0.0920 km/s
Rotation period ? d
Albedo ?
Temperature ~158 K
Spectral type C
Absolute magnitude 7.75

120 Lachesis is a very large and very dark main belt asteroid. As a primitive C-type asteroid it is likely composed of carbonaceous material. It was discovered by Alphonse Borrelly on April 10, 1872 and named after one of the Moirae, or Fates, in Greek mythology. The only observed Lachesean occultation occurred in 1999 and was recorded in the south-western United States.