4000 Hipparchus
From Wikipedia, the free encyclopedia
| Discovery[1] | |
|---|---|
| Discovered by | S. Ueda H. Kaneda |
| Discovery site | Kushiro Obs. |
| Discovery date | 4 January 1989 |
| Designations | |
| (4000) Hipparchus | |
| Pronunciation | /hɪˈpɑːrkəs/[2] |
Named after | Hipparchus[3] (ancient Greek astronomer) |
| 1989 AV · 1963 XA 1975 TW4 · 1977 FZ2 1978 NG8 · 1979 WU4 1984 YX5 · 1987 SD18 | |
| main-belt[1][4] · (middle) background[5] · Astraea[6] | |
| Orbital characteristics[4] | |
| Epoch 27 April 2019 (JD 2458600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 63.50 yr (23,192 d) |
| Aphelion | 2.8835 AU |
| Perihelion | 2.2968 AU |
| 2.5901 AU | |
| Eccentricity | 0.1133 |
| 4.17 yr (1,523 d) | |
| 78.842° | |
| 0° 14m 11.04s / day | |
| Inclination | 2.7163° |
| 318.53° | |
| 173.15° | |
| Physical characteristics | |
| 15.13±4.81 km[7] 17.485±0.032 km[8][9] 18.217±0.094 km[10] 18.87±0.59 km[11] | |
| 3.418±0.001 h[12] | |
| 0.0388[10] 0.046[11] 0.05[7] 0.052[8][9] | |
| 12.60[8][10][11] 12.8[1][4][13] 13.01[7] | |
4000 Hipparchus /hɪˈpɑːrkəs/ is a dark background asteroid from the central regions of the asteroid belt, approximately 17 kilometers (11 miles) in diameter. It was discovered on 4 January 1989, by Japanese astronomers Seiji Ueda and Hiroshi Kaneda at the Kushiro Observatory on Hokkaido, Japan.[1] The likely carbonaceous asteroid has a short rotation period of 3.4 hours.[13] It was named for the ancient Greek astronomer Hipparchus.[3]
Hipparchus is a non-family asteroid from the main belt's background population (according to Nesvorný).[5] Conversely, an alternative application of the hierarchical clustering method found it to be a core member of the Astraea family (according to Milani and Knežević).[6] It orbits the Sun in the central asteroid belt at a distance of 2.3–2.9 AU once every 4 years and 2 months (1,523 days; semi-major axis of 2.59 AU). Its orbit has an eccentricity of 0.11 and an inclination of 3° with respect to the ecliptic.[4] The body's observation arc begins with a precovery taken at the Palomar Observatory in November 1954, or more than 34 years prior to its official discovery observation at Kushiro (399).[1]
Naming
This minor planet was named by IAU's Working Group for Planetary System Nomenclature after the Greek astronomer Hipparchus (c. 190 – c. 120 BC), considered to be the greatest astronomer of ancient times. Hipparchus introduced a systematic and critical approach to both theoretical and observational astronomy. He is also honored by a lunar and a Martian crater (Hipparchus and Hipparchus, respectively).[3] The official naming citation was published by the Minor Planet Center on 21 November 1991 (M.P.C. 19335).[14] The asteroid is one of several early "kilo-numbered" minor planets that were dedicated to renowned scientists or institutions including:[15]
- 1000 Piazzia named for Giuseppe Piazzi, discoverer of Ceres
- 2000 Herschel for William Herschel who discovered Uranus
- 3000 Leonardo for the Italian polymath of the Renaissance, Leonardo da Vinci
4000 Hipparchus is follow by the asteroids 5000 IAU (for the International Astronomical Union), 6000 United Nations (for the United Nations), 7000 Curie (for the pioneers on radioactivity, Marie and Pierre Curie), and 8000 Isaac Newton (for Isaac Newton),[15] while 9000 Hal (after HAL 9000 from the movie 2001: A Space Odyssey) and 10000 Myriostos (after the Greek word for ten-thousandth, and to honor all astronomers) were named based on their direct numeric accordance.
