1447 Utra, provisional designation 1938 BB, is a stony asteroid, slow rotator and suspected tumbler from the central region of the asteroid belt, approximately 12 kilometers in diameter. It was discovered on 26 January 1938, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland.[9] The asteroid was named for the Finnish town of Utra (now a part of Joensuu).[2]
| Discovery[1] | |
|---|---|
| Discovered by | Y. Väisälä |
| Discovery site | Turku Obs. |
| Discovery date | 26 January 1938 |
| Designations | |
| (1447) Utra | |
Named after | Utra (Finnish town)[2] |
| 1938 BB · 1936 SB 1951 KO · A918 FA | |
| main-belt · (middle)[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 98.67 yr (36,038 days) |
| Aphelion | 2.6404 AU |
| Perihelion | 2.4299 AU |
| 2.5352 AU | |
| Eccentricity | 0.0415 |
| 4.04 yr (1,474 days) | |
| 285.64° | |
| 0° 14m 39.12s / day | |
| Inclination | 4.7865° |
| 35.528° | |
| 64.085° | |
| Physical characteristics | |
| Dimensions | 11.83±0.86 km[4] 11.834±0.122 km[5] 12.634±0.103 km[6] 13.26±0.53 km[7] 13.58 km (calculated)[3] |
| 257±30 h[a] | |
| 0.20 (assumed)[3] 0.303±0.038[7] 0.3381±0.0591[6] 0.381±0.058[4] | |
| S[3] | |
| 11.30[4][6][7] · 11.60±0.44[8] · 11.7[1][3] | |
Orbit and classification
editUtra is a S-type asteroid. It orbits the Sun in the central main-belt at a distance of 2.4–2.6 AU once every 4.04 years (1,474 days). Its orbit has an eccentricity of 0.04 and an inclination of 5° with respect to the ecliptic.[1] Utra was first identified as A918 FA at Heidelberg Observatory in 1918. The body's observation arc begins with its official discovery observation at Turku in 1938.[9]
Physical characteristics
editSlow rotator
editIn March 2011, a rotational lightcurve of Utra was obtained from photometric observations by astronomer Luis E. Martinez. Lightcurve analysis gave a long rotation period of 257 hours with a brightness variation of 0.63 magnitude (U=2). This slow rotator is also a suspected tumbler (T0).[a]
Diameter and albedo
editAccording to the surveys carried out by the Japanese Akari satellite and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Utra measures between 11.83 and 13.26 kilometers in diameter, and its surface has an albedo between 0.303 and 0.381.[4][5][6][7] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 13.58 kilometers with an absolute magnitude of 11.7.[3]
Naming
editThis minor planet was named for Utra, a northeastern Finnish town and birthplace of the discoverer.[2] The official naming citation was published by the Minor Planet Center on 30 January 1964 (M.P.C. 2277).[10]
Notes
edit- ^ a b Martinez (2011) web: rotation period 257±30 hours with a brightness amplitude of 0.63 mag. Summary figures for (1447) Utra at Collaborative Asteroid Lightcurve Link (CALL). The referenced website was a non-recoverable dead link.
References
edit- ^ a b c d "JPL Small-Body Database Browser: 1447 Utra (1938 BB)" (2016-11-14 last obs.). Jet Propulsion Laboratory. Retrieved 25 July 2017.
- ^ a b c Schmadel, Lutz D. (2007). "(1447) Utra". Dictionary of Minor Planet Names – (1447) Utra. Springer Berlin Heidelberg. p. 116. doi:10.1007/978-3-540-29925-7_1448. ISBN 978-3-540-00238-3.
- ^ a b c d e f "LCDB Data for (1447) Utra". Asteroid Lightcurve Database (LCDB). Retrieved 4 January 2017.
- ^ 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 Masiero, Joseph R.; Grav, T.; Mainzer, A. K.; Nugent, C. R.; Bauer, J. M.; Stevenson, R.; et al. (August 2014). "Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos". The Astrophysical Journal. 791 (2): 11. arXiv:1406.6645. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121. Retrieved 4 January 2017.
- ^ 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.
- ^ 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. Retrieved 4 January 2017.
- ^ 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. Retrieved 4 January 2017.
- ^ a b "1447 Utra (1938 BB)". Minor Planet Center. Retrieved 4 January 2017.
- ^ Schmadel, Lutz D. "Appendix – Publication Dates of the MPCs". Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008). Springer Berlin Heidelberg. p. 221. doi:10.1007/978-3-642-01965-4. ISBN 978-3-642-01964-7.
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
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
- 1447 Utra at AstDyS-2, Asteroids—Dynamic Site
- 1447 Utra at the JPL Small-Body Database
