(7563) 1988 BC

(7563) 1988 BC
Discovered byT. Kojima
Discovery siteYGCO Chiyoda Stn.
Discovery date16 January 1988
(7563) 1988 BC
1988 BC · 1991 VJ5
main-belt[1][2] · (middle)
Orbital characteristics[2]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc30.03 yr (10,969 d)
Aphelion3.2894 AU
Perihelion2.0689 AU
2.6792 AU
4.39 yr (1,602 d)
0° 13m 29.28s / day
Physical characteristics
Mean diameter
12.04±3.52 km[3]
13.93±0.10 km[4]
15.857±0.103 km[5][6]
16.134±0.099 km[7]
17.27±0.64 km[8]
6.539±0.005 h[9][10]
S (assumed)[9]

(7563) 1988 BC, provisional designation 1988 BC, is a background asteroid from the central region of the asteroid belt, approximately 16 kilometers (10 miles) in diameter. It was discovered on 16 January 1988, by Japanese amateur astronomer Takuo Kojima at the YGCO Chiyoda Station in the Kantō region of Japan.[1] The asteroid has a rotation period of 6.5 hours.[9]

Classification and orbit[]

1988 BC is non-family asteroid of the main belt's background population. It orbits the Sun in the central asteroid belt at a distance of 2.1–3.3 AU once every 4 years and 5 months (1,602 days; semi-major axis of 2.68 AU). Its orbit has an eccentricity of 0.23 and an inclination of 13° with respect to the ecliptic.[2]


As of 2018, 1988 BC remains unnamed.[1]

Physical characteristics[]


In January 2010, a rotational lightcurve of 1988 BC was obtained from photometric observations by Pierre Antonini at the Bédoin Observatory (132) in southeastern France. Lightcurve analysis gave a rotation period of 6.539±0.005 hours with a brightness variation of 0.30 in magnitude (U=3).[10] A previous 2006-observation by American astronomer Brian Warner at his Palmer Divide Observatory in Colorado gave a period of 6.510 hours and an amplitude of 0.24 magnitude (U=3-).[11]

Diameter and albedo[]

According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the asteroid has a low albedo of between 0.048 and 0.08, with a diameter between 12.04 and 17.27 kilometers.[6][7][8]

Despite the results from the space-based observations, the Collaborative Asteroid Lightcurve Link assumes a higher albedo of 0.10 – a compromise between the stony and carbonaceous asteroid populations from the inner and outer main-belt, respectively – and hence calculates a smaller diameter of 12.1 kilometers with an absolute magnitude of 12.7.[9]


  1. ^ a b c d e "7563 (1988 BC)". Minor Planet Center. Retrieved 13 September 2018.
  2. ^ a b c d "JPL Small-Body Database Browser: 7563 (1988 BC)" (2018-01-27 last obs.). Jet Propulsion Laboratory. Archived from the original on 15 December 2019. Retrieved 13 September 2018.
  3. ^ a b c Nugent, C. R.; Mainzer, A.; Masiero, J.; Bauer, J.; Cutri, R. M.; Grav, T.; et al. (December 2015). "NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos". The Astrophysical Journal. 814 (2): 13. arXiv:1509.02522. Bibcode:2015ApJ...814..117N. doi:10.1088/0004-637X/814/2/117. S2CID 9341381.
  4. ^ a b c Nugent, C. R.; Mainzer, A.; Bauer, J.; Cutri, R. M.; Kramer, E. A.; Grav, T.; et al. (September 2016). "NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos". The Astronomical Journal. 152 (3): 12. arXiv:1606.08923. Bibcode:2016AJ....152...63N. doi:10.3847/0004-6256/152/3/63. S2CID 119289027.
  5. ^ a b c Mainzer, A. K.; Bauer, J. M.; Cutri, R. M.; Grav, T.; Kramer, E. A.; Masiero, J. R.; et al. (June 2016). "NEOWISE Diameters and Albedos V1.0". NASA Planetary Data System: EAR-A-COMPIL-5-NEOWISEDIAM-V1.0. Bibcode:2016PDSS..247.....M. Retrieved 13 September 2018.
  6. ^ a b c Masiero, Joseph R.; Grav, T.; Mainzer, A. K.; Nugent, C. R.; Bauer, J. M.; Stevenson, R.; et al. (August 2014). "Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos". The Astrophysical Journal. 791 (2): 11. arXiv:1406.6645. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121. S2CID 119293330.
  7. ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. S2CID 118700974. (catalog)
  8. ^ a b c d Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
  9. ^ a b c d e "LCDB Data for (7563)". Asteroid Lightcurve Database (LCDB). Retrieved 13 September 2018.
  10. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (7563)". Geneva Observatory. Retrieved 13 September 2018.
  11. ^ Warner, Brian D. (December 2006). "Asteroid lightcurve analysis at the Palmer Divide Observatory - March - June 2006". The Minor Planet Bulletin. 33 (4): 85–88. Bibcode:2006MPBu...33...85W. ISSN 1052-8091.

External links[]