| Discovery[1] | |
|---|---|
| Discovered by | C. W. Juels |
| Discovery site | Fountain Hills Obs. |
| Discovery date | 30 November 2000 |
| Designations | |
| (20898) Fountainhills | |
Named after | Fountain Hills[1] (U.S. city in Arizona) |
| 2000 WE147 · 1975 BE 1994 NA1 | |
| main-belt[1][2] · (outer)[2][3] background[4] · ACO[5]: 872 | |
| Orbital characteristics[2] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 66.49yr (24,285 d) |
| Aphelion | 6.1881AU |
| Perihelion | 2.2572 AU |
| 4.2226 AU | |
| Eccentricity | 0.4654 |
| 8.68 yr (3,169 d) | |
| 328.44° | |
| 0° 6m 48.96s / day | |
| Inclination | 45.523° |
| 293.19° | |
| 234.78° | |
| Jupiter MOID | 0.5295 AU |
| TJupiter | 2.3490 |
| Physical characteristics | |
| 37.08 km(derived)[3] 37.31±1.1 km[6] 41.53±0.85 km[7] | |
| 12.84±0.03 h[8] | |
| 0.0200(derived)[3] 0.037±0.007[7] 0.0505±0.003[6] | |
| D[3][5] B–V =0.767±0.008[9] V–R =0.428±0.010[9] V–I =0.826±0.008[9] | |
| 11.0[6] · 11.10[2][7] 12.02[3][8] | |
20898 Fountainhills (provisional designation2000 WE147) is a darkasteroid in acometary orbit (ACO) from the outermost regions of theasteroid belt, approximately 37 kilometers (23 miles) in diameter. It was discovered on 30 November 2000, by American amateur astronomerCharles W. Juels at theFountain Hills Observatory in Arizona, United States.[1] TheD-type asteroid has a rotation period of 12.84 hours.[3] It was named for the city ofFountain Hills, Arizona, in the United States.[1]
Fountainhills is a non-family from the main belt'sbackground population.[4] For an object in the asteroid belt, its orbit is extremely eccentric and highly inclined. With aJupiter tisserand (TJupiter) of less than 3 and with no observablecoma, it is an asteroid in cometary orbit (ACO) and a candidate for being a dormant orextinct comet.[5] It is however, not adamocloid based on current orbital criteria, which typically have a TJupiter of less than 2(also seeList of damocloids).
The asteroid orbits the Sun in theouter main-belt at a distance of 2.3–6.2 AU once every 8 years and 8 months (3,169 days;semi-major axis of 4.22 AU). Its orbit has aneccentricity of 0.47 and aninclination of 46° with respect to theecliptic.[2] The body'sobservation arc begins with aprecovery taken atPalomar Observatory during theDigitized Sky Survey in July 1951, more than 49 years prior to its official discovery observation at Fountain Hills.[1]
Fountainhills is the second most eccentric object as large as it is inside the orbit of Jupiter (after1036 Ganymed), and the most highly inclined object of its size within the orbit of Jupiter. While its aphelion is outside that of Jupiter's orbit, it is so highly inclined that its furthest point from the Sun is far out of the ecliptic.[citation needed]
Fountainhills has been characterized as a darkD-type asteroid in a study of asteroids in cometary orbits using theNordic Optical Telescope atRoque de los Muchachos Observatory on the Canary Island, Spain.[5]
In January 2001, a rotationallightcurve of Fountainhills was obtained from photometric observations by American amateur astronomerBill Holliday at River Oaks Observatory (915) in Texas. Lightcurve analysis gave a well-definedrotation period of 12.84 hours with a brightness amplitude of 0.20magnitude (U=3).[8]
According to the survey carried out by the Infrared Astronomical SatelliteIRAS, and on data obtained by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer, Fountainhills measures between 37.31 and 41.53 kilometers in diameter and its surface has analbedo between 0.037 and 0.0505.[6][7] TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.02 and a diameter of 37.08 kilometers based on anabsolute magnitude of 12.02.[3]
Thisminor planet was named after the town ofFountain Hills, located near theSonoran Desert on the foothills of theMcDowell Mountains, home to one of the world's tallest water fountains. The official naming citation was published by theMinor Planet Center on 9 May 2001 (M.P.C. 42678).[10]
