3184 Raab, provisional designation 1949 QC, is a dark background asteroid and a potentially slow rotator from the central regions of the asteroid belt, approximately 17 kilometers (11 miles) in diameter. It was discovered on 22 August 1949, by South African astronomer Ernest Leonard Johnson at the Union Observatory in Johannesburg. The likely C-type asteroid could have a long rotation period of 275 hours. It was named after Austrian amateur astronomer and software engineer Herbert Raab.[1][4]
| Discovery [1] | |
|---|---|
| Discovered by | Ernest Johnson |
| Discovery site | Johannesburg Obs. |
| Discovery date | 22 August 1949 |
| Designations | |
| (3184) Raab | |
Named after | Herbert Raab [1] (Austrian astronomer) |
| 1949 QC · 1970 GR1 1975 SG · 1980 WF1 | |
| main-belt [1][2] · (middle) background [3] | |
| Orbital characteristics [2] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 68.41 yr (24,988 d) |
| Aphelion | 3.3689 AU |
| Perihelion | 1.9689 AU |
| 2.6689 AU | |
| Eccentricity | 0.2623 |
| 4.36 yr (1,593 d) | |
| 269.05° | |
| 0° 13m 33.96s / day | |
| Inclination | 8.1951° |
| 97.111° | |
| 238.00° | |
| Physical characteristics | |
| 13.25 km (calculated)[4] 15.28±5.62 km[5] 17.49±0.28 km[6] 17.638±0.108 km[7] 18.38±7.54 km[8] 19.280±0.060 km[9] | |
| 274.944±2.9899 h[10] | |
| 0.036±0.004[7] 0.0470±0.0041[9] 0.05±0.04[8] 0.065±0.070[5] 0.086±0.003[6] 0.10 (generic)[4] | |
| C/S (generic)[4] | |
| 12.056±0.002 (R)[10] 12.10[6][9] 12.11±0.30[11] 12.2[2] 12.46[8] 12.51[4] 12.67[5] | |
Orbit and classification
editRaab is a non-family asteroid from the main belt's background population.[3] It orbits the Sun in the central main-belt at a distance of 2.0–3.4 AU once every 4 years and 4 months (1,593 days; semi-major axis of 2.67 AU). Its orbit has an eccentricity of 0.26 and an inclination of 8° with respect to the ecliptic.[2] The body's observation arc begins with its official discovery observation at Johannesburg in August 1949.[1]
Physical characteristics
editThis asteroid's spectral type is unknown. Based on its low albedo, measured by the Wide-field Infrared Survey Explorer (WISE), Raab is possibly C-type asteroid.[2]
Rotation period
editIn December 2011, a rotational lightcurve of Raab was obtained from photometric observations in the R-band by astronomers at the Palomar Transient Factory in California.[10] Lightcurve analysis gave a rotation period of 274.944 hours with a brightness amplitude of 0.09 magnitude. However, the lightcurve is only fragmentary and could be completely wrong (U=1).[4] This makes Raab only a potentially slow rotator rather than a confirmed one. As of 2018, no follow up observations have been published.[2][4]
Diameter and albedo
editAccording to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's WISE telesecope, Raab measures between 15.28 and 19.280 kilometers in diameter and its surface has an albedo between 0.036 and 0.086.[5][6][7][8][9]
The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 – used as a generic compromise between the stony (0.20) and carbonaceous (0.057) asteroids with semi-major axis between 2.6 and 2.7 AU – and consequently calculates a shorter diameter of 13.25 kilometers using on an absolute magnitude of 12.51.[4]
Naming
editThis minor planet was named after Austrian amateur astronomer and software engineer Herbert Raab (born 1969), who developed the astrometric software "Astrometrica". The official naming citation was published by the Minor Planet Center on 3 May 1996 (M.P.C. 27124), following a proposal by Brian Marsden and Gareth Williams.[1][12]
References
edit- ^ a b c d e f "3184 Raab (1949 QC)". Minor Planet Center. Retrieved 2 May 2018.
- ^ a b c d e f "JPL Small-Body Database Browser: 3184 Raab (1949 QC)" (2018-01-20 last obs.). Jet Propulsion Laboratory. Retrieved 2 May 2018.
- ^ a b "Asteroid 3184 Raab – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 29 October 2019.
- ^ a b c d e f g h "LCDB Data for (3184) Raab". Asteroid Lightcurve Database (LCDB). Retrieved 2 May 2018.
- ^ a b c d Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Nugent, C.; et al. (November 2012). "Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids". The Astrophysical Journal Letters. 759 (1): 5. arXiv:1209.5794. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8. S2CID 46350317.
- ^ a b c d Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
- ^ a b c Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. S2CID 118745497.
- ^ a b c d Nugent, C. R.; Mainzer, A.; Bauer, J.; Cutri, R. M.; Kramer, E. A.; Grav, T.; et al. (September 2016). "NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos". The Astronomical Journal. 152 (3): 12. arXiv:1606.08923. Bibcode:2016AJ....152...63N. doi:10.3847/0004-6256/152/3/63.
- ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. S2CID 35447010. (catalog)
- ^ a b c 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.
- ^ 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.
- ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 2 May 2018.
External links
edit- Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
- Dictionary of Minor Planet Names, Google books
- Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
- 3184 Raab at AstDyS-2, Asteroids—Dynamic Site
- 3184 Raab at the JPL Small-Body Database
