8900 AAVSO, provisional designation 1995 UD2, is a stony background asteroid from the central region of the asteroid belt, approximately 5.5 kilometers in diameter. It was discovered by American amateur astronomer Dennis di Cicco at the U.S Sudbury Observatory (817), Massachusetts, on 24 October 1995.[8] The asteroid was named after the American Association of Variable Star Observers (AAVSO).[2]

8900 AAVSO
Discovery [1]
Discovered byD. di Cicco
Discovery siteSudbury Obs. (817)
Discovery date24 October 1995
MPC designation(8900) AAVSO
Named after
(American Association of Variable Star Observers)[2]
1995 UD2 · 1979 UV
1987 SX16 · 1989 EU2
main-belt · (middle)
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc37.37 yr (13,651 days)
Aphelion2.9070 AU
Perihelion2.1657 AU
2.5364 AU
4.04 yr (1,475 days)
0° 14m 38.4s / day
Physical characteristics
Dimensions5.28 km (calculated)[3]
5.792±0.320 km[4][5]
3.8368±0.0005 h[6]
0.20 (assumed)[3]
13.4[1] · 13.75[3] · 13.2[4] · 13.303±0.004 (R)[6] · 13.84±0.28[7]

Orbit and classificationEdit

AAVSO is a non-family asteroid from the main belt's background population. It orbits the Sun in the central main-belt at a distance of 2.2–2.9 AU once every 4.04 years (1,475 days). Its orbit has an eccentricity of 0.15 and an inclination of 9° with respect to the ecliptic.[1] The first precovery was obtained at Kleť Observatory in 1979, extending the asteroid's observation arc by 16 years prior to its discovery.[8]


This minor planet was named after the American Association of Variable Star Observers (AAVSO), an astronomical pro-am organization that promotes the study of variable stars to both amateur and professional astronomers, maintaining the largest database of variable star observations in the world.[2]

AAVSO was founded in 1911 by amateur astronomer William Tyler Olcott (1873–1936), based on a suggestion by Edward Charles Pickering's (1846–1919), after whom the minor planet 784 Pickeringia is named.[2] The official naming citation was published by the Minor Planet Center on 1 May 2003 (M.P.C. 48388).[9]

Physical characteristicsEdit


In May 2010, a rotational lightcurve of AAVSO was obtained at the Palomar Transient Factory in California. Lightcurve analysis gave a rotation period of 3.8368 hours with a brightness variation of 0.43 in magnitude (U=2).[6]

Diameter and albedoEdit

According to the NEOWISE mission of NASA's space-based Wide-field Infrared Survey Explorer, AAVSO measures 5.8 kilometers in diameter and its surface has an albedo of 0.28,[4][5] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 5.3 kilometers.[3]


  1. ^ a b c d "JPL Small-Body Database Browser: 8900 AAVSO (1995 UD2)" (2017-03-04 last obs.). Jet Propulsion Laboratory. Retrieved 22 June 2017.
  2. ^ a b c d Schmadel, Lutz D. (2006). "(8900) Aavso [2.54, 0.14, 8.7]". Dictionary of Minor Planet Names – (8900) AAVSO, Addendum to Fifth Edition: 2003–2005. Springer Berlin Heidelberg. p. 40. doi:10.1007/978-3-540-34361-5_277. ISBN 978-3-540-34360-8.
  3. ^ a b c d e "LCDB Data for (8900) AAVSO". Asteroid Lightcurve Database (LCDB). Retrieved 26 April 2016.
  4. ^ 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. Retrieved 26 April 2016.
  5. ^ a b c Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 4 December 2016.
  6. ^ a b c Waszczak, Adam; Chang, Chan-Kao; Ofek, Eran O.; Laher, Russ; Masci, Frank; Levitan, David; et al. (September 2015). "Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry". The Astronomical Journal. 150 (3): 35. arXiv:1504.04041. Bibcode:2015AJ....150...75W. doi:10.1088/0004-6256/150/3/75. Retrieved 26 April 2016.
  7. ^ Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 26 April 2016.
  8. ^ a b "8900 AAVSO (1995 UD2)". Minor Planet Center. Retrieved 26 April 2016.
  9. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 26 April 2016.

External linksEdit