9617 Grahamchapman

9617 Grahamchapman
Discovery [1]
Discovered byUESAC
Discovery siteLa Silla Obs.
Discovery date17 March 1993
(9617) Grahamchapman
Named after
Graham Chapman
(Monty Python)[2]
1993 FA5 · 1991 RN18
main-belt · Flora[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc64.84 yr (23,681 days)
Aphelion2.4770 AU
Perihelion1.9711 AU
2.2240 AU
3.32 yr (1,211 days)
0° 17m 49.92s / day
Known satellites1 [4][5]
Physical characteristics
Dimensions2.840 km[6][7]
2.849 km[8]
2.85 km (taken)[3]
2.2856 h[4]
2.28561±0.00006 h[9]
2.28561±0.00009 h[9]
14.37±0.23 (R)[9] · 14.43±0.2 (R)[4] · 14.7[1] · 14.88[6] · 14.97±0.078[3][8] · 15.03±0.34[10]

9617 Grahamchapman, provisional designation 1993 FA5, is a binary[4] Florian asteroid from the inner regions of the asteroid belt, approximately 2.8 kilometers in diameter.

The asteroid was discovered on 17 March 1993, during the Uppsala–ESO Survey of Asteroids and Comets (UESAC) at ESO's La Silla Observatory in northern Chile.[11] It was named for actor and Monty Python member, Graham Chapman.[2]

Orbit and classification[]

Grahamchapman is a member of the Flora family, one of the largest collisional groups of stony asteroids. It orbits the Sun in the inner main-belt at a distance of 2.0–2.5 AU once every 3 years and 4 months (1,211 days). Its orbit has an eccentricity of 0.11 and an inclination of 6° with respect to the ecliptic.[1] A first precovery was taken at Palomar Observatory in 1951, extending the body's observation arc by 42 years prior to its official discovery observation at La Silla.[11]

Physical characteristics[]

Diameter and albedo[]

According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Grahamchapman measures 2.84 kilometers in diameter and its surface has an albedo of 0.245.[6] The Collaborative Asteroid Lightcurve Link agrees with Petr Pravec's revised NEOWISE data and gives an albedo of 0.224 with a diameter of 2.85 kilometers with an absolute magnitude of 14.97.[3][8]

Asteroid moon[]

In February 2006, observations by the Ondřejov NEO Photometric Program determined that Grahamchapman is orbited by a minor-planet moon. The satellite is about a quarter the size of Grahamchapman, and orbits it about once every 19 hours, 23 minutes, and 5 seconds.[4][5]

Rotation period and shape[]

The lightcurve study also showed that Grahamchapman itself has a rotation period of 2.28561 hours with a brightness variation of 0.10 magnitude (U=3).[9] A second photometric observation in December 2008, gave an identical period with an amplitude of 0.11 magnitude (U=3).[9] A low brightness amplitude typically indicates that the body has a nearly spheroidal shape.


This minor planet is named after the comic actor Graham Chapman (1941–1989).[2] It is the first in a series of six asteroids carrying the names of members of the Monty Python comedy troupe, the others being 9618 Johncleese, 9619 Terrygilliam, 9620 Ericidle, 9621 Michaelpalin and 9622 Terryjones. The approved naming citation was published by the Minor Planet Center on 20 March 2000 (M.P.C. 39653).[12]


  1. ^ a b c d "JPL Small-Body Database Browser: 9617 Grahamchapman (1993 FA5)" (2016-06-08 last obs.). Jet Propulsion Laboratory. Retrieved 22 June 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(9617) Grahamchapman". Dictionary of Minor Planet Names – (9617) Grahamchapman. Springer Berlin Heidelberg. p. 700. doi:10.1007/978-3-540-29925-7_7599. ISBN 978-3-540-00238-3.
  3. ^ a b c d e "LCDB Data for (9617) Grahamchapman". Asteroid Lightcurve Database (LCDB). Retrieved 8 September 2016.
  4. ^ a b c d e Pray, D.; Pravec, P.; Kusnirak, P.; Reddy, V.; Dyvig, R.; Gajdos, S. (March 2006). "(9617) Grahamchapman". Central Bureau Electronic Telegrams. 414 (414): 1. Bibcode:2006CBET..414....1P. Retrieved 8 September 2016.
  5. ^ a b Johnston, Robert. "(9617) Grahamchapman". johnstonsarchive.net. Retrieved 8 September 2015.
  6. ^ 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.
  7. ^ a b 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 8 September 2016.
  8. ^ a b c d Pravec, Petr; Harris, Alan W.; Kusnirák, Peter; Galád, Adrián; Hornoch, Kamil (September 2012). "Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations". Icarus. 221 (1): 365–387. Bibcode:2012Icar..221..365P. doi:10.1016/j.icarus.2012.07.026. Retrieved 8 September 2016.
  9. ^ a b c d e Pravec, P.; Scheirich, P.; Vokrouhlický, D.; Harris, A. W.; Kusnirák, P.; Hornoch, K.; et al. (March 2012). "Binary asteroid population. 2. Anisotropic distribution of orbit poles of small, inner main-belt binaries". Icarus. 218 (1): 125–143. Bibcode:2012Icar..218..125P. doi:10.1016/j.icarus.2011.11.026. Retrieved 8 September 2016.
  10. ^ 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 8 September 2016.
  11. ^ a b "9617 Grahamchapman (1993 FA5)". Minor Planet Center. Retrieved 8 September 2016.
  12. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 8 September 2016.

External links[]