| Discovery[1] | |
|---|---|
| Discovered by | T. Kojima |
| Discovery site | YGCO Chiyoda Stn. |
| Discovery date | 29 November 1988 |
| Designations | |
| (4949) Akasofu | |
Named after | Syun-Ichi Akasofu (geophysicist)[2] |
| 1988 WE · 1978 YE 1981 RL5 · 1981 SV6 | |
| main-belt · Flora[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 38.45 yr (14,044 days) |
| Aphelion | 2.6555AU |
| Perihelion | 1.8904 AU |
| 2.2729 AU | |
| Eccentricity | 0.1683 |
| 3.43yr (1,252 days) | |
| 163.34° | |
| 0° 17m 15.36s / day | |
| Inclination | 4.8106° |
| 108.70° | |
| 275.40° | |
| Physical characteristics | |
| Dimensions | 4.460±0.181 km[4][5] 5.67 km(calculated)[3] |
| 2.6798±0.0002h[6] 2.6800±0.0003 h[a] | |
| 0.24(assumed)[3] 0.322±0.055[4][5] | |
| S[3] | |
| 13.4[1][3] · 13.6[4] · 13.49±0.14[7] | |
4949 Akasofu, provisional designation1988 WE, is a stony Floraasteroid from the inner regions of theasteroid belt, approximately 5 kilometers in diameter. It was discovered by Japanese amateur astronomerTakuo Kojima at theYGCO Chiyoda Station in Japan on 29 November 1988.[8] The asteroid was named for Japanese geophysicistSyun-Ichi Akasofu
Akasofu is a member of theFlora family, one of the largest groups ofstony asteroids in the main-belt. It orbits the Sun in theinner main-belt at a distance of 1.9–2.7 AU once every 3 years and 5 months (1,252 days). Its orbit has aneccentricity of 0.17 and aninclination of 5° with respect to theecliptic.[1] In 1978, it was first identified as1978 YE at thePurple Mountain Observatory, extending the body'sobservation arc by 10 years prior to its official discovery observation at Chiyoda Station.[8]
According to the survey carried out by theNEOWISE mission of NASA's space-basedWide-field Infrared Survey Explorer,Akasofu measures 4.5 kilometers in diameter and its surface has analbedo of 0.32,[4][5] while theCollaborative Asteroid Lightcurve Link assumes an intermediate albedo of 0.24 – which derives from8 Flora, the largest member and namesake of this orbital family – and calculates a diameter of 5.7 kilometers with anabsolute magnitude of 13.4.[3]
In October 2005, a rotationallightcurve ofAkasofu was obtained from photometric observations made by David Higgins at Hunters Hill Observatory, Australia. It showed arotation period of2.6798 hours with a brightness variation of 0.10 inmagnitude (U=3).[6]
Observations by Czech astronomerPetr Pravec in March 2007, gave another well-defined and concurring lightcurve with a period of2.6800 hours and an amplitude of 0.15 in magnitude (U=3).[a]
Thisminor planet was named in honor of Japanese-born geophysicistSyun-Ichi Akasofu (born 1930), professor atUniversity of Alaska Fairbanks. He was the director of theInternational Arctic Research Center from 1998 to 2007, and is known for studies of theaurora borealis.[2] The official naming citation was published by theMinor Planet Center on 30 March 2010 (M.P.C. 69491).[9]
