| Discovery[1] | |
|---|---|
| Discovered by | G. Neujmin |
| Discovery site | Simeiz Obs. |
| Discovery date | 21 September 1928 |
| Designations | |
| (1123) Shapleya | |
Named after | Harlow Shapley (American astronomer)[2] |
| 1928 ST · 1974 QQ2 2016 FJ6 | |
| main-belt · Flora[3] | |
| Orbital characteristics[1] | |
| Epoch 16 February 2017 (JD 2457800.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 87.81 yr (32,073 days) |
| Aphelion | 2.5741AU |
| Perihelion | 1.8758 AU |
| 2.2250 AU | |
| Eccentricity | 0.1569 |
| 3.32yr (1,212 days) | |
| 207.68° | |
| 0° 17m 49.2s / day | |
| Inclination | 6.4212° |
| 79.889° | |
| 317.60° | |
| Physical characteristics | |
| Dimensions | 10.93±2.29 km[4] 11.282±0.136 km[5] 12.003±0.092 km[6] 12.08 km(taken)[3] 12.084 km[7] 12.32±0.84 km[8] |
| 20h(dated)[9] 24 h(dated)[10] 52.92±0.01 h[11] | |
| 0.2600±0.0630[6] 0.274±0.044[8] 0.278±0.037[5] 0.2797[7] 0.36±0.19[4] | |
| S[3] | |
| 11.55±0.29[12] · 11.59±0.13[3][7][9] · 11.60[4] · 11.7[1][6][8] | |
1123 Shapleya, provisional designation1928 ST, is a stony Florianasteroid from the inner regions of theasteroid belt, approximately 11 kilometers in diameter. It was discovered on 21 September 1928, by Russian astronomerGrigory Neujmin atSimeiz Observatory on the Crimean peninsula.[13] It was named after American astronomerHarlow Shapley.[2]
Shapleya is aS-type asteroid and member of theFlora family of stony asteroids, one of the largest families of the main belt. It orbits the Sun at a distance of 1.9–2.6 AU once every 3 years and 4 months (1,212 days). Its orbit has aneccentricity of 0.16 and aninclination of 6° with respect to theecliptic.[1] As noprecoveries were taken, and no prior identifications were made, the body'sobservation arc begins with its official discovery observation at Simeiz.[13]
In November 2011, the so-far best rated rotationallightcurve of was obtained by American astronomerRobert Stephens at the Center for Solar System Studies in California. Lightcurve analysis gave arotation period of 52.92 hours with a brightness variation of 0.38magnitude (U=3-),[11] superseding observations byWiesław Z. Wiśniewski and a group of French, Italian and Swiss astronomers, that gave a shorter period of 20 and 24 hours, respectively (U=2/2).[9][10]Shapleya has a relativelyslow rotation period, as most minor planets have a spin rate between 2 and 20 hours.
According to the surveys carried out by the JapaneseAkari satellite and NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Shapleya measures between 10.93 and 12.32 kilometers in diameter, and its surface has analbedo between 0.26 and 0.36.[4][5][6][8] TheCollaborative Asteroid Lightcurve Link adoptsPetr Pravec's revised WISE data, that is, an albedo of 0.2797 and a diameter of 12.084 kilometers with anabsolute magnitude of 11.59.[3][7]
Thisminor planet was named by the discoverer afterHarlow Shapley (1885–1972), American astronomer and director ofHarvard Observatory in Cambridge, Massachusetts.[2] The lunar craterShapley and theShapley Supercluster are also named after him. Naming citation was first mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 105).[2]
