_Afra.png) Modelled shape ofAfra from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 6 December 1929 |
| Designations | |
| (1187) Afra | |
Named after | unknown[2] |
| 1929 XC | |
| Orbital characteristics[3] | |
| Epoch 31 May 2020 (JD 2459000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 90.16yr (32,932 d) |
| Aphelion | 3.2285AU |
| Perihelion | 2.0523 AU |
| 2.6404 AU | |
| Eccentricity | 0.2227 |
| 4.29 yr (1,567 d) | |
| 52.040° | |
| 0° 13m 46.92s / day | |
| Inclination | 10.697° |
| 327.16° | |
| 74.956° | |
| Physical characteristics | |
| SMASS =X[3] | |
| 11.50[1][3] | |
1187 Afra (prov. designation:1929 XC) is a darkbackground asteroid from the central regions of theasteroid belt. It was discovered by German astronomerKarl Reinmuth atHeidelberg Observatory on 6 December 1929.[1] TheX-type asteroid has arotation period of 14.1 hours and measures approximately 32 kilometers (20 miles) in diameter. The origin of the asteroid's name remains unknown.
Afra is a non-family asteroid of the main belt'sbackground population when applying thehierarchical clustering method to itsproper orbital elements.[4][5] It orbits the Sun in thecentral asteroid belt at a distance of 2.1–3.2 AU once every 4 years and 3 months (1,567 days;semi-major axis of 2.64 AU). Its orbit has aneccentricity of 0.22 and aninclination of 11° with respect to theecliptic.[3] The body'sobservation arc begins at Heidelberg in January 1930, seven weeks after its official discovery observation.[1]
It is not known to what person, group of persons, or occurrence the name "Afra" refers to.[2]
Among the many thousands ofnamed minor planets,Afra is one of 120 asteroids, for which no official naming citation has been published. All of these low-numbered asteroids have numbers between164 Eva and1514 Ricouxa and were discovered between 1876 and the 1930s, predominantly by astronomersAuguste Charlois,Johann Palisa,Max Wolf andKarl Reinmuth.[13]
Thelightcurve ofAfra shows a periodicity of14.09±0.02 hours, during which time the brightness of the object varies by0.40±0.02 in magnitude.[11][14]
