| Discovery[1] | |
|---|---|
| Discovered by | C. Shoemaker E. Shoemaker |
| Discovery site | Palomar Obs. |
| Discovery date | 23 October 1984 |
| Designations | |
| (3700) Geowilliams | |
Named after | George E. Williams[1] (Australian geologist) |
| 1984 UL2 · 1973 YF2 1977 UJ | |
| main-belt[1][2] · (inner)[3] background[4] | |
| Orbital characteristics[2] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 43.54yr (15,902 d) |
| Aphelion | 2.9602AU |
| Perihelion | 1.8695 AU |
| 2.4148 AU | |
| Eccentricity | 0.2258 |
| 3.75 yr (1,371 d) | |
| 293.18° | |
| 0° 15m 45.36s / day | |
| Inclination | 12.121° |
| 289.16° | |
| 153.06° | |
| Physical characteristics | |
| 7.712±0.130 km[5] 7.74±1.83 km[6] 7.753±0.152 km[7] 8.70±0.30 km[8] 8.82±0.86 km[9] 8.97 km(calculated)[3] | |
| 14.383±0.0183 h[10] 14.387±0.003 h[a] | |
| 0.20(assumed)[3] 0.227±0.045[9] 0.23±0.13[6] 0.233±0.033[8] 0.2970±0.0516[5] | |
| SMASS =Sk[2] | |
| 12.443±0.002(R)[10] 12.50[5][8][9] 12.6[2][3] 12.89[6] 12.94±0.46[11] | |
3700 Geowilliams, provisional designation1984 UL2, is a stony backgroundasteroid from the inner regions of theasteroid belt, approximately 8 kilometers (5 miles) in diameter. It was discovered on 23 October 1984, by American astronomer coupleCarolyn andEugene Shoemaker at thePalomar Observatory in California, United States.[1] TheSk-subtype has arotation period of 14.38 hours. It was named for Australian geologistGeorge E. Williams.[1]
Geowilliams is a non-family asteroid from the main belt'sbackground population.[4] It orbits the Sun in theinner main-belt at a distance of 1.9–3.0 AU once every 3 years and 9 months (1,371 days;semi-major axis of 2.41 AU). Its orbit has aneccentricity of 0.23 and aninclination of 12° with respect to theecliptic.[2] The body'sobservation arc begins with its first observation as1973 YF2 atCrimea-Nauchnij in December 1973, almost 11 years prior to its official discovery observation at Palomar.[1]
In theSMASS classification,Geowilliams is a Sk-subtype that transitions between the commonS-type asteroid and theK-type asteroid. The latterspectral type is often found among members of theEos family.[2]
In January 2008, a rotationallightcurve ofGeowilliams was obtained fromphotometric observations by Australian amateur astronomerDavid Higgins at the Hunters Hill Observatory (E14). Lightcurve analysis gave a well-definedrotation period of 14.387 hours with a brightness variation of 0.40magnitude (U=3).[a] In July 2010, a similar period of 14.383 hours and an amplitude of 0.42 was measured at thePalomar Transient Factory in California (U=2).[10]
According to the surveys carried out by the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Geowilliams measures between 7.712 and 8.82 kilometers in diameter and its surface has analbedo between 0.227 and 0.297.[5][6][7][8][9]
TheCollaborative Asteroid Lightcurve Link assumes a standard albedo for a stony asteroid of 0.20, and calculates a diameter of 8.97 kilometers based on anabsolute magnitude of 12.6.[3]
Thisminor planet was named after Australian geologistGeorge E. Williams who discovered theAcraman crater when he worked forBHP inSouth Australia. The old 90-kilometer impact structure isone of the largest meteoriteimpact craters known on Earth and the largest one on the Australian continent.[1] The official naming citation was published by theMinor Planet Center on 2 February 1988 (M.P.C. 12810).[12]
