| Discovery[1] | |
|---|---|
| Discovered by | E. Bowell |
| Discovery site | Anderson Mesa Stn. |
| Discovery date | 11 February 1980 |
| Designations | |
| (2542) Calpurnia | |
| Pronunciation | /kælˈpɜːrniə/[2] |
Named after | Calpurnia(Julius Caesar's wife)[3] |
| 1980 CF · 1972 XN2 1976 OE | |
| main-belt · (outer) | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 62.57 yr (22,854 days) |
| Aphelion | 3.3624AU |
| Perihelion | 2.8997 AU |
| 3.1311 AU | |
| Eccentricity | 0.0739 |
| 5.54yr (2,024 days) | |
| 248.88° | |
| 0° 10m 40.44s / day | |
| Inclination | 4.6207° |
| 145.71° | |
| 47.930° | |
| Physical characteristics | |
| Dimensions | 18±1 km[4] 20.854±0.281 km[5] 27.6±2.3 km[6] |
| 0.0639±0.012[6] 0.102±0.007[5] 0.15±0.02[4] | |
| C[7] | |
| 11.6[1] | |
2542 Calpurnia, provisionally designated1980 CF, is a carbonaceous high-albedoasteroid from the outer regions of theasteroid belt, approximately 20 kilometers in diameter. It was discovered on 11 February 1980, by American astronomerEdward Bowell atAnderson Mesa Station, Flagstaff, United States.[8] The asteroid was named after Julius Caesar's wife,Calpurnia.[3]
Calpurnia orbits the Sun in theouter main-belt at a distance of 2.9–3.4 AU once every 5 years and 6 months (2,024 days). Its orbit has aneccentricity of 0.07 and aninclination of 5° with respect to theecliptic.[1] In 1954, a firstprecovery was taken at thePalomar Observatory in California, extending the body'sobservation arc by 26 prior to its official discovery observation at Anderson Mesa.[8]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS and NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Calpurnia measures 27.6 and 20.854 kilometers in diameter, and its surface has analbedo of 0.0639 and 0.102, respectively.[6][5] It has anabsolute magnitude of 11.6.[1]
Near-infrared spectroscopic observations, however, gave a higher albedo of 0.15 with a subsequently shorter diameter of 18 kilometers.Calpurnia has a featureless surface with up to 60% amorphous magnesiumpyroxenes that might explain the high albedo for an carbonaceous outer-belt asteroid.[4]
As of 2017, no rotationallightcurve has been obtained. The body'sspectral type, as well as itsrotation period and shape remain unknown.[1][9]
Thisminor planet was named afterCalpurnia, the last wife of Julius Caesar.[3] The approved naming citation was published by theMinor Planet Center on 8 April 1982 (M.P.C. 6834).[10]
