_Angara.png) Modelled shape of Angara from its
lightcurve | |
| Discovery [1] | |
|---|---|
| Discovered by | L. Chernykh |
| Discovery site | Crimean Astrophysical Obs. |
| Discovery date | 1 April 1970 |
| Designations | |
| (1957) Angara | |
Named after |
Angara River (Siberian river) [2] |
| 1970 GF · 1962 WG1 1969 AA | |
| main-belt · Eos [3] | |
| Orbital characteristics [1] | |
| Epoch 4 September 2017 ( JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 60.58 yr (22,126 days) |
| Aphelion | 3.1828 AU |
| Perihelion | 2.8338 AU |
| 3.0083 AU | |
| Eccentricity | 0.0580 |
| 5.22 yr (1,906 days) | |
| 345.36 ° | |
| 0° 11m 20.04s / day | |
| Inclination | 11.191° |
| 50.702° | |
| 209.03° | |
| Physical characteristics | |
| Dimensions | 17.907±0.108 km
[4] 18.189±0.229 km [5] 18.38 km (derived) [3] 21.44±0.70 km [6] 30.41±0.58 km [7] |
| 3.67 h [8] | |
| 0.055±0.006
[7] 0.111±0.008 [6] 0.14 (assumed) [3] 0.1438±0.0310 [5] | |
|
S
[3]
[8] B–V = 0.900 [1] U–B = 0.380 [1] | |
| 11.16±0.34 [9] · 11.36 [1] [6] [7] · 11.43 [3] [5] [8] | |
1957 Angara ( prov. designation: 1970 GF) is a stony Eos asteroid from the outer regions of the asteroid belt, approximately 18 kilometers (11 miles) in diameter. It was discovered on 1 April 1970, by Soviet astronomer Lyudmila Chernykh at the Crimean Astrophysical Observatory in Nauchnyj, and named after the Siberian Angara River. [2] [10]
Classification and orbit
Angara is a member of the Eos family, well known for mostly being of a silicaceous composition. It orbits the Sun in the outer main-belt at a distance of 2.8–3.2 AU once every 5 years and 3 months (1,906 days). Its orbit has an eccentricity of 0.06 and an inclination of 11 ° with respect to the ecliptic. [1] A first precovery was taken at Goethe Link Observatory in 1956, extending the body's observation arc by 14 years prior to its official discovery observation at Nauchnyj. [10]
Naming
This minor planet was named for the over 1000-mile long Siberian Angara River that drains Lake Baikal. [2] The official naming citation was published by the Minor Planet Center on 30 June 1977 ( M.P.C. 4190). [11]
Physical characteristics
In December 1983, a rotational lightcurve of Angara was obtained from photometric observations by American astronomer Richard Binzel. Lightcurve analysis gave a well-define rotation period of 3.67 hours with a brightness amplitude of 0.52 magnitude, indicative of a non-spheroidal shape ( U=3). [8] Binzel also classified the body as a stony S-type asteroid. [8]
According to the surveys carried out by the Japanese Akari satellite and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Angara measures between 17.907 and 30.41 kilometers in diameter and its surface has an albedo between 0.055 and 0.1438. [4] [5] [6] [7] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony Eoan asteroids of 0.14 – taken from the family's largest member and namesake, 221 Eos – and derives a diameter of 18.38 kilometers with an absolute magnitude of 11.43. [3]
References
- ^ a b c d e f "JPL Small-Body Database Browser: 1957 Angara (1970 GF)" (2017-06-02 last obs.). Jet Propulsion Laboratory. Retrieved 2 July 2017.
- ^ a b c Schmadel, Lutz D. (2007). "(1957) Angara". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 157. doi: 10.1007/978-3-540-29925-7_1958. ISBN 978-3-540-00238-3.
- ^ a b c d e f "LCDB Data for (1957) Angara". Asteroid Lightcurve Database (LCDB). Retrieved 4 April 2017.
- ^ a b 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. Retrieved 4 April 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 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 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 April 2017.
- ^ a b c d e Binzel, R. P. (October 1987). "A photoelectric survey of 130 asteroids". Icarus. 72 (1): 135–208. Bibcode: 1987Icar...72..135B. doi: 10.1016/0019-1035(87)90125-4. ISSN 0019-1035. Retrieved 4 April 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 April 2017.
- ^ a b "1957 Angara (1970 GF)". Minor Planet Center. Retrieved 4 April 2017.
- ^ Schmadel, Lutz D. (2009). "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
- Asteroid Lightcurve Database (LCDB), query form ( info Archived 21 July 2011 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
- 1957 Angara at AstDyS-2, Asteroids—Dynamic Site
- 1957 Angara at the JPL Small-Body Database
