| Discovery[1] | |
|---|---|
| Discovered by | H. Debehogne |
| Discovery site | La Silla Obs. |
| Discovery date | 18 September 1982 |
| Designations | |
| (11474)1982 SM2 | |
| 1982 SM2 · 1995 KD | |
| main-belt · Baptistina[2] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 32.59 yr (11,905 days) |
| Aphelion | 2.7224AU |
| Perihelion | 1.8294 AU |
| 2.2759 AU | |
| Eccentricity | 0.1962 |
| 3.43yr (1,254 days) | |
| 76.029° | |
| 0° 17m 13.56s / day | |
| Inclination | 5.4069° |
| 348.59° | |
| 355.61° | |
| Physical characteristics | |
| Dimensions | 5.71 km(calculated)[2] |
| 1917.2214±2716h[3] | |
| 0.057(assumed)[2] | |
| C[2] | |
| 14.493±0.001(R)[3] · 14.7[1] · 14.94[2] · 14.94±0.61[4] | |
(11474) 1982 SM2 is a carbonaceous Baptistinaasteroid and potentiallyslow rotator from the inner regions of theasteroid belt, approximately 6 kilometers in diameter. It was discovered on 18 September 1982, by Belgian astronomerHenri Debehogne atESO'La Silla Observatory in northern Chile.[5]
TheC-type asteroid belongs to the smallBaptistina family. It orbits the Sun at a distance of 1.8–2.7 AU once every 3 years and 5 months (1,254 days). Its orbit has aneccentricity of 0.20 and aninclination of 5° with respect to theecliptic.[1] As noprecoveries were taken, and no prior identifications were made, the asteroid'sobservation arc begins with its official discovery observation.[5]
In September 2013, a rotationallightcurve of this asteroid was obtained from photometric observations in the R-band at thePalomar Transient Factory in California. It gave an exceptionally longrotation period of 1917 hours with a brightness amplitude of 0.04magnitude (U=1).[3] However, the fragmentary light-curve has received a low quality rating by theCollaborative Asteroid Lightcurve Link (CALL) which means that the result could be completely wrong(also seepotentially slow rotator).[2][3]
CALL assumes a standardalbedo for carbonaceous asteroids of 0.057 and calculates a diameter of 5.71 kilometers, based on anabsolute magnitude of 14.49.[2]
Thisminor planet wasnumbered by theMinor Planet Center on 28 September 1999.[6] As of 2018, it has not beennamed.[5]
