(11474) 1982 SM2 is a carbonaceous Baptistina asteroid and potentially slow rotator from the inner regions of the asteroid belt, approximately 6 kilometers in diameter. It was discovered on 18 September 1982, by Belgian astronomer Henri Debehogne at ESO‘ La Silla Observatory in northern Chile.[5]
| 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 | 2.7224 AU |
| Perihelion | 1.8294 AU |
| 2.2759 AU | |
| Eccentricity | 0.1962 |
| 3.43 yr (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±2716 h[3] | |
| 0.057 (assumed)[2] | |
| C[2] | |
| 14.493±0.001 (R)[3] · 14.7[1] · 14.94[2] · 14.94±0.61[4] | |
The C-type asteroid belongs to the small Baptistina 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 an eccentricity of 0.20 and an inclination of 5° with respect to the ecliptic.[1] As no precoveries were taken, and no prior identifications were made, the asteroid’s observation arc begins with its official discovery observation.[5]
In September 2013, a rotational lightcurve of this asteroid was obtained from photometric observations in the R-band at the Palomar Transient Factory in California. It gave an exceptionally long rotation period of 1917 hours with a brightness amplitude of 0.04 magnitude (U=1).[3] However, the fragmentary light-curve has received a low quality rating by the Collaborative Asteroid Lightcurve Link (CALL) which means that the result could be completely wrong (also see potentially slow rotator).[2][3]
CALL assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 5.71 kilometers, based on an absolute magnitude of 14.49.[2]
This minor planet was numbered by the Minor Planet Center on 28 September 1999.[6] As of 2018, it has not been named.[5]
- ^ a b c d “JPL Small-Body Database Browser: 11474 (1982 SM2)” (2015-04-23 last obs.). Jet Propulsion Laboratory. Retrieved 26 May 2017.
- ^ a b c d e f g “LCDB Data for (11474)”. Asteroid Lightcurve Database (LCDB). Retrieved 16 December 2016.
- ^ a b c d Waszczak, Adam; Chang, Chan-Kao; Ofek, Eran O.; Laher, Russ; Masci, Frank; Levitan, David; et al. (September 2015). “Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry”. The Astronomical Journal. 150 (3): 35. arXiv:1504.04041. Bibcode:2015AJ….150…75W. doi:10.1088/0004-6256/150/3/75. S2CID 8342929. Retrieved 16 December 2016.
- ^ Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). “Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 – Preliminary results”. Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261…34V. doi:10.1016/j.icarus.2015.08.007. S2CID 53493339. Retrieved 16 December 2016.
- ^ a b c “11474 (1982 SM2)”. Minor Planet Center. Retrieved 16 December 2016.
- ^ “MPC/MPO/MPS Archive”. Minor Planet Center. Retrieved 24 February 2018.
- Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
- Dictionary of Minor Planet Names, Google books
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- Discovery Circumstances: Numbered Minor Planets (10001)-(15000) – Minor Planet Center
- (11474) 1982 SM2 at AstDyS-2, Asteroids—Dynamic Site
- (11474) 1982 SM2 at the JPL Small-Body Database
