| Discovery[1] | |
|---|---|
| Discovered by | L. Boyer |
| Discovery site | Algiers Obs. |
| Discovery date | 16 March 1936 |
| Designations | |
| (1392) Pierre | |
Named after | Pierre[2](discoverer's nephew) |
| 1936 FO · 1938 SZ 1955 TZ · 1959 SH A917 UB | |
| main-belt[1][3] · (middle) Eunomia[4][5] · background[6] | |
| Orbital characteristics[3] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 81.30 yr (29,695 days) |
| Aphelion | 3.1355AU |
| Perihelion | 2.0788 AU |
| 2.6071 AU | |
| Eccentricity | 0.2026 |
| 4.21yr (1,538 days) | |
| 244.35° | |
| 0° 14m 2.76s / day | |
| Inclination | 12.263° |
| 358.24° | |
| 44.290° | |
| Physical characteristics | |
| 26.16±0.34 km[7] 26.44±1.6 km[5][8] 27.02±5.29 km[9] 28.94±8.81 km[10] | |
| 18 h[11] | |
| 0.04±0.01[9] 0.04±0.02[10] 0.0519±0.007[5][8] 0.054±0.002[7] | |
| Tholen =DX[3][5] · C[12] B–V = 0.757[3] U–B = 0.258[3] | |
| 11.72[3][5][7][8][10] 11.9[1] | |
1392 Pierre, provisional designation1936 FO, is a dark, dynamical Eunomianasteroid from the central regions of theasteroid belt, approximately 26 kilometers (16 mi) in diameter. It was discovered on 16 March 1936, by astronomerLouis Boyer at theAlgiers Observatory in Algeria, North Africa.[1] The asteroid was named after the discoverer's nephew, Pierre.[2]
Pierre is a dynamical member of theEunomia family (502), a prominentfamily ofstony asteroids and the largest one in the intermediate main belt with more than 5,000 members.[4][5]Pierre's spectral type is different from that of the Eunomia family(see below) and possibly aninterloper rather than a true family member. When applying thehierarchical clustering method to itsproper orbital elements,Pierre is a non-family asteroid of the main belt'sbackground population.[6]
It orbits the Sun in thecentral main-belt at a distance of 2.1–3.1 AU once every 4 years and 3 months (1,538 days). Its orbit has aneccentricity of 0.20 and aninclination of 12° with respect to theecliptic.[3] The asteroid was first observed asA917 UB atSimeiz Observatory in October 1917. The body'sobservation arc begins with its official discovery observation at Algiers in March 1936.[1]
Thisminor planet was named after Pierre, a nephew of the discovererLouis Boyer. The officialnaming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 126).[2]
Pierre has been characterized as a carbonaceousC-type asteroid byPan-STARRS photometric survey.[12] In theTholen classification, the asteroid's spectral type is ambiguous, closest to a darkD-type and somewhat similar to a genericX-type asteroid.[3] Conversely, the Eunomia family consists ofS-type asteroids.[13]: 23
In August 1984, a first rotationallightcurve ofPierre was obtained from photometric observations with theESO 1-metre telescope at theLa Silla Observatory in Chile. Lightcurve analysis gave arotation period of 18 hours with a brightness variation of 0.09magnitude (U=2).[11] A poorly rated lightcurve byPierre Antonini in January 2007, gave a period of 24 hours with an amplitude of 0.05 magnitude.[14]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Pierre measures between 26.16 and 28.94 kilometers in diameter and its surface has analbedo between 0.04 and 0.054.[7][8][9][10] TheCollaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.0519 and a diameter of 26.44 kilometers based on anabsolute magnitude of 11.72.[5][8]
