3202 Graff, provisional designation A908 AA, is a carbonaceous Hilda asteroid from the outermost region of the asteroid belt, approximately 36 kilometers in diameter. It was discovered on 3 January 1908, by German astronomer Max Wolf at Heidelberg Observatory in southern Germany.[7] The asteroid was named after astronomer Gareth V. Williams.[2]
Discovery [1] | |
---|---|
Discovered by | M. F. Wolf |
Discovery site | Heidelberg Obs. |
Discovery date | 3 January 1908 |
Designations | |
(3202) Graff | |
Named after | Gareth V. Williams (astronomer)[2] |
A908 AA · 1981 ES13 | |
main-belt[1] · Hilda [3] | |
Orbital characteristics [1] | |
Epoch 4 September 2017 (JD 2458000.5) | |
Uncertainty parameter 0 | |
Observation arc | 109.02 yr (39,819 days) |
Aphelion | 4.3883 AU |
Perihelion | 3.4843 AU |
3.9363 AU | |
Eccentricity | 0.1148 |
7.81 yr (2,853 days) | |
295.10° | |
0° 7m 34.32s / day | |
Inclination | 11.107° |
205.14° | |
268.81° | |
Physical characteristics | |
Dimensions | 35.914±0.244[4] 36.78 km (calculated)[3] |
17.32±0.02 h[5] | |
0.055±0.013[4] 0.057 (assumed)[3] | |
D [6] · C [3] | |
10.9[1][3] · 11.31±0.28[6] | |
Graff belongs to the Hilda family of asteroids, which are in a 3:2 orbital resonance with the giant planet Jupiter. It orbits the Sun in the outer main-belt at a distance of 3.5–4.4 AU once every 7 years and 10 months (2,853 days). Its orbit has an eccentricity of 0.11 and an inclination of 11° with respect to the ecliptic.[1] The asteroid's observation arc begins 3 weeks after its discovery with its first used observation at Heidelberg.[7]
The dark C-type asteroid is classified as a rare D-type by Pan-STARRS' large-scale survey,[6]
In July 2015, a rotational lightcurve of Graff was obtained by astronomer Robert Stephens at the Center for Solar System Studies. It gave a well-defined rotation period of 17.32±0.02 hours with a brightness variation of 0.18 in magnitude (U=3-).[5]
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Graff measures 35.9 kilometers in diameter and its surface has an albedo of 0.055.[4] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 36.8 kilometers with an absolute magnitude of 10.9.[3]
This minor planet was named after English-born astronomer Gareth "Graff" Vaughan Williams (born 1965), who identified various low-numbered asteroids among bodies that had been given provisional designations. His work at the Minor Planet Center (MPC) has received much recognition.[2]
The official naming citation was published by the Minor Planet Center on 10 April 1990 (M.P.C. 16245),[8] based on a suggestion by long-time MPC director Brian G. Marsden (1937–2000) and by Conrad M. Bardwell (1926–2010), associate director of the MPC and who made the identification for this body.[2] The minor planets 1615 Bardwell and 1877 Marsden were named in honor of these two prominent astronomers at the MPC.