Hubble Space Telescope image of 2002 AW197 taken in 2006
| |
| Discovery[1][2] | |
|---|---|
| Discovered by | Palomar Obs. (team) |
| Discovery site | Palomar Obs. |
| Discovery date | 10 January 2002 |
| Designations | |
| 2002 AW197 | |
| TNO[3] · cubewano[4] p-DP[5] · extended[6] distant[1] | |
| Orbital characteristics[3] | |
| Epoch 31 May 2020 (JD 2459000.5) | |
| Uncertainty parameter3 | |
| Observation arc | 21.23 yr (7,756 d) |
| Earliest precovery date | 29 December 1997 |
| Aphelion | 53.161 AU |
| Perihelion | 40.922 AU |
| 47.042 AU | |
| Eccentricity | 0.13009 |
| 322.65 yr (117,848 d) | |
| 294.532° | |
| 0° 0m 10.998s / day | |
| Inclination | 24.451° |
| 297.606° | |
| ≈ 5 May 2078[7] ±4 days | |
| 297.494° | |
| Physical characteristics | |
Mean diameter | 768±39 km[8] 734±116 km[9] 700±50 km[10][11] 886km[12] |
| 8.87±0.01 h[13] 8.78±0.05 h[14] 8.86±0.01 h[15] | |
| 0.112+0.012 −0.011[8] | |
| IR[16][17] · (moderately red) B–V = 0.920±0.020[18] V–R = 0.560±0.020[18] V–I = 1.170±0.010[17] | |
| 20.0 (opposition)[19][20] | |
| 3.568±0.046 (V)[21] 3.156±0.059 (R)[22] 3.3 (assumed)[3] | |
(55565) 2002 AW197 (provisional designation 2002 AW197) is a classical, non-resonant trans-Neptunian object from the Kuiper belt in the outermost region of the Solar System, also known as a cubewano. With a likely diameter of at least 600 kilometers (400 miles), it is approximately tied with 2002 MS4 and 2013 FY27 (to within measurement uncertainties) as the largest unnamed object in the Solar System. It was discovered at Palomar Observatory in 2002.
Its rotation period is 8.8 hours and it is a moderately red color.[16] Tancredi notes that photometric observations suggest that it is a spheroid with a high albedo and small albedo spots.[23] However, its low albedo suggests it does not have planetary geology, as it should if it were a dwarf planet.
2002 AW197 was discovered on 10 January 2002, by astronomers at the Palomar Observatory in California.[1] Astronomers involved in the discovery were Michael Brown, Chad Trujillo, Eleanor Helin, Michael Hicks, Kenneth Lawrence and Steven H. Pravdo.[2] It is located near the Kuiper cliff.
2002 AW197 orbits the Sun at a distance of 40.9–53.2 AU once every 322.6 years (over 117,800 days; semi-major axis of 47 AU). Its orbit has an eccentricity of 0.13 and an inclination of 24° with respect to the ecliptic.[3] The body's observation arc begins with a precovery taken at Haleakala-NEAT/GEODSS (566) in December 1997, more than 4 years prior to its official discovery observation at Palomar.[1] At 45.4 AU from the Sun,[19] it continues to slowly approach the Sun until its perihelion passage at 41.1 AU in May 2078.[7]
Combined observations of thermal emissions by the Herschel Space Observatory and Spitzer Space Telescope give a diameter of 768+39
−38 km and a geometric albedo of 0.112+0.012
−0.011.[8]
ESO analysis of spectra reveals a strong red slope and no presence of water ice[24] (in contrast to Quaoar, also red) suggesting organic material (see comparison of colours and typical composition inferred from spectra of the TNOs).
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| TNO classes |
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| Dwarf planets (moons) |
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| Sednoids |
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