| Discovery[1] | |
|---|---|
| Discovered by | C.-I. Lagerkvist |
| Discovery site | Mount Stromlo Obs. |
| Discovery date | 19 April 1976 |
| Designations | |
| (2114) Wallenquist | |
Named after | Åke Wallenquist (Swedish astronomer)[2] |
| 1976 HA · 1930 DG 1942 LD · 1953 GZ 1964 FA · 1970 EO3 1970 EZ2 | |
| main-belt · Themis[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 63.51 yr (23,198 days) |
| Aphelion | 3.6508AU |
| Perihelion | 2.7467 AU |
| 3.1987 AU | |
| Eccentricity | 0.1413 |
| 5.72yr (2,090 days) | |
| 91.271° | |
| 0° 10m 20.28s / day | |
| Inclination | 0.5558° |
| 1.5530° | |
| 216.98° | |
| Physical characteristics | |
| Dimensions | 21.12±1.26 km[4] 22.558±0.079[5] 23.008±0.190 km[6] 27.45 km(derived)[3] 27.67±2.3 km(IRAS:2)[7] |
| 5.49±0.01h[8] 5.5078±0.0009 h[9] 5.510±0.005 h[10] | |
| 0.0447(derived)[3] 0.0838±0.016(IRAS:2)[7] 0.1216±0.0099[6] 0.145±0.019[5] 0.149±0.020[4] | |
| S[3] | |
| 11.1[7][4][6] · 11.749±0.002(R)[9] · 11.8[1][3] · 11.87±0.23[11] | |
2114 Wallenquist, provisional designation1976 HA, is a Themistianasteroid from the outer region of theasteroid belt, approximately 28 kilometers in diameter. It was discovered by Swedish astronomerClaes-Ingvar Lagerkvist at the AustralianMount Stromlo Observatory near Canberra, on 19 April 1976.[12]
Wallenquist is a member of theThemis family, a dynamical family of outer-belt asteroids with nearly coplanar ecliptical orbits. It orbits the Sun in theouter main-belt at a distance of 2.7–3.7 AU once every 5 years and 9 months (2,090 days). Its orbit has aneccentricity of 0.14 and aninclination of 1° with respect to theecliptic.[1] The first used observation was made at the U.S.Goethe Link Observatory in 1953, extending the asteroid'sobservation arc by 23 years prior to its discovery.[12]
In April 2010, a rotationallightcurve ofWallenquist obtained by American astronomerRobert Stephens at theGoat Mountain Astronomical Research Station (GMARS,G79), California, gave a well-definedrotation period of5.510 hours with a brightness amplitude of 0.22magnitude (U=3).[10]
Two other observations, by French astronomerRené Roy at Blauvac Observatory (627), France, and by astronomers at the U.S.Palomar Transient Factory, gave a period of5.49±0.01 and5.5078±0.0009, with an amplitude of 0.30 and 0.23, respectively (U=2/2).[8][9]
According to the surveys carried out by the Infrared Astronomical Satellite,IRAS, the JapaneseAkari satellite, and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Wallenquist measures between 21.1 and 27.6 kilometers in diameter while its surface has analbedo in the range of 0.08 and 0.15.[4][5][6][7]
TheCollaborative Asteroid Lightcurve Link (CALL) derives an even lower albedo of 0.04 and calculates a diameter of 27.5 kilometer. Despite its low albedo, CALL characterizes the body as aS-type rather than a darkerC-type asteroid.[3]
Thisminor planet was named in honor of Swedish astronomerÅke Wallenquist (1904–1994), former director of theKvistaberg Station, after which the minor planet3331 Kvistaberg is named.[2]
After his retirement Wallenquist continued to researchdark matter in open clusters at theUppsala Astronomical Observatory. He co-discovered the near-Earth Amor asteroid1980 Tezcatlipoca during his stay at thePalomar Observatory in California in 1950.[2] The officialnaming citation was published by theMinor Planet Center on 1 February 1979 (M.P.C. 4645).[13]
