47 Aglaja

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47 Aglaja
Discovery
Discovered by Robert Luther
Discovery date September 15, 1857
Designations
Named after Aglaea
Minor planet category Main belt
Orbital characteristics[1]
Epoch December 31, 2006 (JD 2454100.5)
Aphelion 488.740 Gm (3.267 AU)
Perihelion 372.222 Gm (2.488 AU)
Semi-major axis 430.481 Gm (2.878 AU)
Eccentricity 0.135
Orbital period 1,782.960 d (4.88 a)
Average orbital speed 17.48 km/s
Mean anomaly 225.007°
Inclination 4.985°
Longitude of ascending node 3.244°
Argument of perihelion 314.589°
Physical characteristics
Dimensions 141.90 ± 8.72[2] km
Mass (3.25 ± 1.68) × 1018[2] kg
Mean density 2.17 ± 1.19[2] g/cm3
Equatorial surface gravity 0.0355 m/s²
Escape velocity 0.0671 km/s
Rotation period 13.175[3] h
Albedo 0.080 [4]
Temperature ~164 K
Spectral type C (Tholen)
B[5] (SMASS II)
Absolute magnitude (H) 7.84

47 Aglaja /əˈɡl.ə/ is a large, dark main belt asteroid. It was discovered by Robert Luther on September 15, 1857 from Düsseldorf.[6] The name was chosen by the Philosophical Faculty of the University of Bonn and refers to Aglaea, one of the Charites in Greek mythology.[7]

Based upon its spectrum, 47 Aglaja is listed as a C-type asteroid under the Tholen classification taxonomy, indicating a carbonaceous composition. The SMASS classification system rates it as a rare B-type asteroid. There is a broad absorption feature at 1 μm that is associated with the presence of magnetite and is what gives the asteroid its blue tint.[5]

On September 16, 1984, the star SAO 146599 was occulted by 47 Aglaja. This event was observed from 13 sites in the continental United States, allowing a cross-sectional profile to be determined. Based upon this study, the asteroid has a diameter of 136.4 ± 1.2 km. The geometric albedo at the time of the occultation was 0.071 ± 0.002.[8]

Photometric observations of this asteroid at the Organ Mesa Observatory in Las Cruces, New Mexico during 2012 gave a light curve with a period of 13.175 ± 0.002 hours and a brightness variation of 0.09 ± 0.01 in magnitude. This result is in agreement with previous studies.[3]

References[edit]

  1. ^ Yeomans, Donald K., "47 Aglaja", JPL Small-Body Database Browser (NASA Jet Propulsion Laboratory), retrieved 2013-04-07. 
  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 (October 2012), "Rotation Period Determinations for 47 Aglaja, 252 Clementina, 611 Valeria, 627 Charis, and 756 Lilliana", Planetary and Space Science 39: 220–222, Bibcode:2012MPBu...39..220P. 
  4. ^ Asteroid Data Sets
  5. ^ a b Yang, Bin; Jewitt, David (September 2010), "Identification of Magnetite in B-type Asteroids", The Astronomical Journal 140 (3): 692–698, arXiv:1006.5110, Bibcode:2010AJ....140..692Y, doi:10.1088/0004-6256/140/3/692. 
  6. ^ "Numbered Minor Planets 1–5000", Discovery Circumstances (IAU Minor Planet center), retrieved 2013-04-07. 
  7. ^ Schmadel, Lutz (2003), Dictionary of minor planet names (fifth ed.), Germany: Springer, p. 19, ISBN 3-540-00238-3, retrieved 2008-12-29. 
  8. ^ Millis, R. L. et al. (October 1989), "The diameter, shape, albedo, and rotation of 47 Aglaja", Icarus 81: 375–385, Bibcode:1989Icar...81..375M, doi:10.1016/0019-1035(89)90058-4.  See Table 1.

External links[edit]