_Prometheus.png) Shape model ofPrometheus from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | C. J. van Houten I. van Houten-G. T. Gehrels (Palomar–Leiden survey) |
| Discovery site | Palomar Obs. |
| Discovery date | 24 September 1960 |
| Designations | |
| (1809) Prometheus | |
| Pronunciation | /prəˈmiːθiːəs/[2] |
Named after | ΠρομηθεύςPromētheys (Greek mythology)[3] |
| 2522 P-L · 1943 EA1 1955 SW · 1955 VA 1965 UR | |
| main-belt · (outer) | |
| Adjectives | Promethean, -ian/prəˈmiːθiːən/[4] |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 61.53 yr (22,473 days) |
| Aphelion | 3.2256AU |
| Perihelion | 2.6245 AU |
| 2.9251 AU | |
| Eccentricity | 0.1027 |
| 5.00yr (1,827 days) | |
| 163.57° | |
| 0° 11m 49.2s / day | |
| Inclination | 3.2585° |
| 99.484° | |
| 231.33° | |
| Physical characteristics | |
| Dimensions | 14.212±0.097 km[5] |
| 0.126±0.010[5] | |
| 11.7[1] | |
1809 Prometheus/prəˈmiːθiːəs/ is anasteroid from the outer region of theasteroid belt, approximately 14 kilometers in diameter. Discovered during thePalomar–Leiden survey in 1960, it was given theprovisional designation2522 P-L and named afterPrometheus from Greek mythology.[3]
Prometheus orbits the Sun in theouter main-belt at a distance of 2.6–3.2 AU once every 5.00 years (1,827 days). Its orbit has aneccentricity of 0.10 and aninclination of 3° with respect to theecliptic.[1]
It was discovered on 24 September 1960, by the Dutch astronomer coupleIngrid andCornelis Johannes van Houten at Leiden, on photographic plates taken by Dutch–American astronomerTom Gehrels at Palomar, California, in the United States.[6] On the same night, the team of astronomers discovered several other minor planets including1810 Epimetheus.
Prometheus was first identified as1943 EA1 at the HungarianKonkoly Observatory in 1943. In 1955, its first used observation was taken atGoethe Link Observatory, when it was identified as1955 SW, extending the body'sobservation arc by 5 years prior to its official discovery observation.[6]
Thesurvey designation "P-L" stands forPalomar–Leiden, named after Palomar Observatory andLeiden Observatory, which collaborated on the fruitfulPalomar–Leiden survey in the 1960s. Gehrels used Palomar'sSamuel Oschin telescope (also known as the 48-inch Schmidt Telescope), and shipped thephotographic plates to Ingrid and Cornelis van Houten at Leiden, whereastrometry was carried out. The trio are credited with the discovery of several thousand minor planets.[7]
Thisminor planet was named forPrometheus, aTitan from Greek mythology, who stole the fire from the gods. The name has also been given to amoon of Saturn,Prometheus (moon), discovered by theVoyager 1 spacecraft in 1980.[3] The asteroid1810 Epimetheus is named after his brother. The officialnaming citation was published by theMinor Planet Center on 20 February 1976 (M.P.C. 3934).[8]
According to the surveys carried out by NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Prometheus measures 14.2 kilometers in diameter, and its surface has analbedo of 0.126.[5] As of 2017, itsspectral type,rotation period and shape remain unknown.
