| Discovery[1] | |
|---|---|
| Discovered by | T. B. Spahr |
| Discovery site | Catalina Stn. |
| Discovery date | 5 August 1994 |
| Designations | |
| (7784) Watterson | |
Named after | Bill Watterson (cartoonist)[2] |
| 1994 PL | |
| main-belt · Phocaea[3][4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 63.56 yr (23,217 days) |
| Aphelion | 2.8025AU |
| Perihelion | 1.7348 AU |
| 2.2686 AU | |
| Eccentricity | 0.2353 |
| 3.42yr (1,248 days) | |
| 280.49° | |
| Inclination | 23.350° |
| 220.66° | |
| 107.04° | |
| Physical characteristics | |
| Dimensions | 5.53 km(calculated)[3] 5.556±0.070 km[5][6] |
| 2.539±0.001h[a] | |
| 0.189±0.022[5][6] 0.23(assumed)[3] | |
| S[3] | |
| 13.5[1][3] · 13.7[5] | |
7784 Watterson, provisional designation1994 PL, is a stony Phocaeaasteroid from the inner regions of theasteroid belt, approximately 6 kilometers in diameter. It was discovered by American astronomerTimothy Spahr at the U.S.Catalina Station, Arizona, on 5 August 1994.[2] The asteroid was named after cartoonistBill Watterson.[2]
TheS-type asteroid is a member of thePhocaea family (701),[4] a group of asteroids with similar orbital characteristics. It orbits the Sun in theinner main-belt at a distance of 1.7–2.8 AU once every 3 years and 5 months (1,248 days). Its orbit has aneccentricity of 0.24 and aninclination of 23° with respect to theecliptic.[1]
In 2011, a photometriclightcurve analysis by astronomerBrian Skiff gave arotation period of2.539 hours with a relatively low brightness amplitude of 0.10magnitude, indicative of a nearly spheroidal shape (U=3-).[a]
According to the surveys carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer (WISE),Watterson has analbedo of 0.19 and a diameter of 5.6 kilometers.[5] TheCollaborative Asteroid Lightcurve Link agrees with WISE's observations and assumes a slightly higher albedo of 0.23 and calculates a diameter of 5.5 kilometers.[3]
Thisminor planet is named afterBill Watterson (born 1958), cartoonist of the daily comic stripCalvin and Hobbes. Syndicated from 1985 to 1995, this strip is fondly remembered and treasured by the discoverer, and helped him stay awake and sane on long observing nights and during the trials and tribulations of graduate school.[2]
