| Discovery[1] | |
|---|---|
| Discovered by | E. Delporte |
| Discovery site | Uccle Observatory |
| Discovery date | 21 September 1941 |
| Designations | |
| (1543) Bourgeois | |
Named after | Paul Bourgeois[2] (Belgian astronomer) |
| 1941 SJ · A911 MF | |
| main-belt · (middle)[3] background[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 75.81 yr (27,689 days) |
| Aphelion | 3.4854AU |
| Perihelion | 1.7812 AU |
| 2.6333 AU | |
| Eccentricity | 0.3236 |
| 4.27yr (1,561 days) | |
| 307.06° | |
| 0° 13m 50.52s / day | |
| Inclination | 11.021° |
| 287.95° | |
| 25.799° | |
| Physical characteristics | |
| Dimensions | 11.985±0.673 km[5] 16.73 km(calculated)[3] |
| 2.48±0.01h[6] | |
| 0.1(assumed)[3] 0.214±0.033[5] | |
| S/C(assumed)[3] | |
| 11.90[5] · 12.0[1][3] · 12.06±0.18[7] | |
1543 Bourgeois (provisional designation1941 SJ) is a stonyasteroid from the centralasteroid belt'sbackground population, approximately 12 kilometers in diameter. It was discovered on 21 September 1941, by astronomerEugène Delporte at theRoyal Observatory of Belgium in Uccle.[8] The asteroid was named after Belgian astronomerPaul Bourgeois.[2]
Bourgeois is a non-family asteroid from the main belt'sbackground population.[4] It orbits the Sun in thecentral asteroid belt at a distance of 1.8–3.5 AU once every 4 years and 3 months (1,561 days). Its orbit has aneccentricity of 0.32 and aninclination of 11° with respect to theecliptic.[1]
The asteroid was first identified asA911 MF atJohannesburg Observatory in June 1911. The body'sobservation arc begins at Istanbul Observatory (080), eight days prior to its official discovery observation at Uccle.[8]
Nospectral type has been determined. The Lightcurve Data Base considers Bourgeois equally likely to be of astony orcarbonaceous, while albedo measurements byWide-field Infrared Survey Explorer suggest that it is a stonyS-type asteroid(see below).[3]
In August 2005, a rotationallightcurve of Bourgeois was obtained from photometric observations by French amateur astronomerLaurent Bernasconi. Analysis of the fragmentary lightcurve gave arotation period of 2.48 hours with a brightness amplitude of 0.03magnitude (U=1).[6] As of 2017, no secure period has been obtained.[3]
According to the survey carried out by theNEOWISE mission of NASA's WISE telescope, Bourgeois measures 11.985 kilometers in diameter and its surface has analbedo of 0.214.[5] TheCollaborative Asteroid Lightcurve Link assumes an albedo of 0.1 – a compromise albedo between the stony (0.20) and carbonaceous (0.057) types, used as a default for asteroids with a semi-major axis between 2.6 and 2.7 AU – and calculates a diameter of 16.73 kilometers based on anabsolute magnitude of 12.0.[3]
Thisminor planet was named in memory ofPaul Bourgeois (1898–1974), director of thediscovering observatory at Uccle, professor at theFree University of Brussels, crediteddiscoverer of asteroid1547 Nele, author of various publications inastrometry, astrophysics,meridian astronomy and stellar statistics.[2] The officialnaming citation was published by theMinor Planet Center on 20 February 1976 (M.P.C. 3930).[9]
