74 Galatea

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For the moon of Neptune, see Galatea (moon).
74 Galatea
Discovery
Discovered by Ernst Wilhelm Tempel
Discovery date August 29, 1862
Designations
Alternative names  
Minor planet category Main belt
Orbital characteristics[1]
Epoch December 31, 2006 (JD 2454100.5)
Aphelion 515.376 Gm (3.445 AU)
Perihelion 315.937 Gm (2.112 AU)
Semi-major axis 415.657 Gm (2.778 AU)
Eccentricity 0.240
Orbital period 1691.658 d (4.63 a)
Average orbital speed 17.61 km/s
Mean anomaly 36.838°
Inclination 4.075°
Longitude of ascending node 197.313°
Argument of perihelion 174.519°
Physical characteristics
Dimensions 120.67 ± 7.15[2] km
Mass (6.13 ± 5.36) × 1018[2] kg
Mean density 6.66 ± 5.94[2] g/cm3
Equatorial surface gravity 0.0332 m/s²
Escape velocity 0.0628 km/s
Rotation period 17.270[3] h
Albedo 0.043 [4]
Temperature ~167 K
Spectral type C[5]
Absolute magnitude (H) 8.66

74 Galatea (/ˈɡæləˈtə/ GAL-ə-TEE) is a large main-belt asteroid. Its surface is very dark in color. Galatea was found by the prolific comet discoverer Ernst Tempel on August 29, 1862, in Marseilles, France. It was his third asteroid discovery. It is named after one of the two Galateas in Greek mythology. A stellar occultation by Galatea was observed on September 8, 1987. The name Galatea has also been given to one of Neptune's satellites.

Photometric observations of this asteroid made during 2008 at the Organ Mesa Observatory in Las Cruces, New Mexico gave a light curve with a period of 17.270 ± 0.002 hours and a brightness variation of 0.08 ± 0.01 in magnitude. The curve displays four minima and four maxima.[3]

References[edit]

  1. ^ Yeomans, Donald K., "74 Galatea", JPL Small-Body Database Browser (NASA Jet Propulsion Laboratory), retrieved 2013-03-30. 
  2. ^ a b c Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science 73: 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009.  See Table 1.
  3. ^ a b Pilcher, Frederick (September 2008), "Period Determinations for 26 Proserpina, 34 Circe 74 Galatea, 143 Adria, 272 Antonia, 419 Aurelia, and 557 Violetta", Bulletin of the Minor Planets Section of the Association of Lunar and Planetary Observers 35 (3): 135–138, Bibcode:2008MPBu...35..135P. 
  4. ^ Asteroid Data Sets
  5. ^ *JPL Small-Body Database Browser