_Richilde.png) Shape model ofRichilde from itslightcurve | |
| Discovery[1][2] | |
|---|---|
| Discovered by | M. F. Wolf |
| Discovery site | Heidelberg Obs. |
| Discovery date | 1 January 1932 |
| Designations | |
| (1214) Richilde | |
Named after | unknown[3] |
| 1932 AA · 1930 QD 1961 PC | |
| main-belt · (middle)[4] background[5] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 86.52 yr (31,602 days) |
| Aphelion | 3.0319AU |
| Perihelion | 2.3881 AU |
| 2.7100 AU | |
| Eccentricity | 0.1188 |
| 4.46yr (1,629 days) | |
| 207.11° | |
| 0° 13m 15.24s / day | |
| Inclination | 9.8345° |
| 285.92° | |
| 32.580° | |
| Physical characteristics | |
| Dimensions | 30.70±12.73 km[6] 33.26±8.39 km[7] 33.651±8.835 km[8] 34.134±0.253 km[9] 34.94±0.50 km[10] 35.22 km(derived)[4] 35.29±3.2 km[11] 36.668±0.575 km[12] 39.58±11.00 km[13] |
| 9.860h[14] 9.86687±0.00005 h[15] 9.870±0.001 h[16] | |
| 0.044±0.051[13] 0.048±0.015[12] 0.0517(derived)[4] 0.0518±0.0853[8] 0.0550±0.0055[9] 0.06±0.02[7] 0.0619±0.013[11] 0.064±0.002[10] 0.07±0.04[6] | |
| SMASS =Xk[1] · P[9] | |
| 10.90[10][11] · 11.03[13] · 11.09[8] · 11.09±0.40[17] · 11.10[4][7][9][14] · 11.20[1][6] | |
1214 Richilde, provisional designation1932 AA, is a dark backgroundasteroid from the central regions of theasteroid belt, approximately 35 kilometers in diameter. It was discovered byMax Wolf atHeidelberg Observatory in 1932. Any reference of the asteroid's name to a person is unknown.[2][3]
Richilde was discovered on 1 January 1932, by German astronomerMax Wolf at theHeidelberg-Königstuhl State Observatory in southwest Germany.[2] Five nights later, on 6 January 1932, it was independently discovered by Japanese astronomer K. Nakamura at Kwasan Observatory (377), Kyoto.[3] TheMinor Planet Center only recognizes the first discoverer.[2] The body'sobservation arc begins with its first observation as1930 QD atUccle Observatory in August 1930, approximately 16 months prior to its official discovery observation at Heidelberg.[2]
Richilde is a non-family asteroid from the main-belt'sbackground population.[5] It orbits the Sun in thecentral asteroid belt at a distance of 2.4–3.0 AU once every 4 years and 6 months (1,629 days;semi-major axis of 2.71 AU). Its orbit has aneccentricity of 0.12 and aninclination of 10° with respect to theecliptic.[1]
In theSMASS,Richilde is a Xk-subtype, that transitions from theX-type to the rareK-type asteroids,[1] while theWide-field Infrared Survey Explorer (WISE) characterizes the body as a primitiveP-type asteroid.[4][9]
In the 1990s, a rotationallightcurve ofRichilde was first obtained from photometric observations by astronomers using theESO 1-metre telescope at theLa Silla Observatory in Chile. Lightcurve analysis gave a well-definedrotation period of 9.860 hours with a brightness variation of 0.32magnitude (U=3).[14] In October 2006, a concurring period of 9.870 hours and an amplitude of 0.31 was measured by French amateur astronomer Raymond Poncy (U=3-).[16]
In 2011, a modeled lightcurve using data from the Uppsala Asteroid Photometric Catalogue (UAPC) and other sources gave a period 9.86687 hours, as well as a partialspin axis of (n.a.°, –59.0°) inecliptic coordinates (λ, β).[15]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA's WISE telescope,Richilde measures between 30.70 and 39.58 kilometers in diameter and its surface has analbedo between 0.044 and 0.07.[6][7][8][9][10][11][12][13]
TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0517 and a diameter of 35.22 kilometers based on anabsolute magnitude of 11.10.[4]
Thisminor planet is named after a common German female name. Any reference of this name to a person or occurrence is unknown (AN 247, 153).[3]
Among the many thousands ofnamed minor planets,Richilde is one of 120 asteroids, for which no official naming citation has been published. All of these asteroids have low numbers between164 Eva and1514 Ricouxa and were discovered between 1876 and the 1930s, predominantly by astronomersAuguste Charlois,Johann Palisa,Max Wolf andKarl Reinmuth.[18]
