9617 Grahamchapman

Lore & Background

9617 Grahamchapman 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. A first precovery was taken at Palomar Observatory in 1951, extending the body's observation arc by 42 years prior to its official discovery. It is a member of the Flora family, one of the largest collisional groups of stony asteroids, and 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), with an eccentricity of 0.11 and an inclination of 6°.

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. 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). A second photometric observation in December 2008 gave an identical period with an amplitude of 0.11 magnitude (U=3). A low brightness amplitude typically indicates that the body has a nearly spheroidal shape.

The minor planet is named after the comic actor Graham Chapman (1941–1989). 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).

Reader's Guide

The significance of 9617 Grahamchapman lies in its dual nature as both a scientifically interesting binary asteroid and a cultural touchstone. As a binary system, it contributes to the study of asteroid satellites, with its moon discovered in 2006 by the Ondřejov NEO Photometric Program. The asteroid's physical characteristics, including a diameter of about 2.8 kilometers and a nearly spheroidal shape inferred from low brightness variation, were measured by surveys such as NEOWISE and collaborative lightcurve studies. Its membership in the Flora family places it among a large group of stony asteroids in the inner main-belt.

Culturally, Grahamchapman is the first of six asteroids named after Monty Python members, honoring the comic actor Graham Chapman. This naming, published on 20 March 2000, links astronomical discovery to popular culture, making the asteroid a memorable entry in the minor planet catalog. The asteroid's discovery during the Uppsala–ESO Survey of Asteroids and Comets at La Silla Observatory, and its precovery dating back to 1951, highlight the collaborative and long-term nature of asteroid observation. Its legacy is as a representative of both scientific research into binary asteroids and the tradition of naming celestial bodies after influential figures.

Did You Know?

• 9617 Grahamchapman is a binary asteroid with a moon about one-quarter its size, discovered in February 2006.
• A precovery image of the asteroid was taken at Palomar Observatory in 1951, 42 years before its official discovery.
• The asteroid's rotation period is 2.28561 hours, with a low brightness amplitude suggesting a nearly spheroidal shape.