4391 Balodis
| Discovery [1] | |
|---|---|
| Discovered by | N. Chernykh |
| Discovery site | Crimea–Nauchnyj |
| Discovery date | 21 August 1977 |
| Designations | |
| 4391 Balodis | |
Named after | Jānis Balodis (geodesist)[2] |
| 1977 QW2 · 1977 RR2 1980 GZ | |
| main-belt · Erigone [3] | |
| Orbital characteristics [1] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 38.61 yr (14,104 days) |
| Aphelion | 2.9009 AU |
| Perihelion | 1.8777 AU |
| 2.3893 AU | |
| Eccentricity | 0.2141 |
| 3.69 yr (1,349 days) | |
| 223.9123° | |
| 0° 16m 0.84s / day | |
| Inclination | 5.3504° |
| 190.3077° | |
| 108.2601° | |
| Physical characteristics | |
| Dimensions | 3.36±0.17 km[4] 8.05 km (calculated)[3] |
| 3.448±0.001 h[5] | |
| 0.393±0.072[4] 0.057 (assumed)[3] | |
| C [3] | |
| 14.2[1][3] 14.00[4] 14.37±0.36[6] | |
4391 Balodis, provisional designation 1977 QW2, is a dark and rare Erigone asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. It was discovered by Soviet–Russian astronomer Nikolai Chernykh at the Crimean Astrophysical Observatory in Nauchnyj, on the Crimean peninsula, on 21 August 1977.[7]
The C-type asteroid orbits the Sun at a distance of 1.9–2.9 AU once every 3 years and 8 months (1,348 days).[1] Based on its orbital elements, the Collaborative Asteroid Lightcurve Link (CALL) classifies the asteroid as a member of the Erigone family, which is named after its largest member and namesake, 163 Erigone, also a dark body of carbonaceous composition.[3] Its orbit has an eccentricity of 0.21 and an inclination of 5° with respect to the ecliptic.[1]
According to observations by NASA's space-based Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid measures 3.4 kilometers in diameter, and its surface has an exceptionally high albedo of 0.40.[4] However, the CALL assumes a much lower albedo of 0.06, a typical value for a carbonaceous asteroid, and calculates a diameter of 8.4 kilometers, as the lower the albedo (reflectivity) the larger the body's diameter at a constant absolute magnitude (brightness).[3]
A rotational light-curve was obtained by Italian astronomer Albino Carbognani from photometric observations taken in July 2010, at the Astronomical Observatory of the Autonomous Region of the Aosta Valley (OAVdA) in Italy. It showed rotation period of 3.448±0.001 hours with a brightness amplitude of 0.29 in magnitude (U=2).[5]
The minor planet was named after Latvian cosmic geodesist Jānis Balodis, head of the Astronomical Observatory at University of Latvia. His research includes astrometry, observations of artificial satellites using laser, as well as computational methods for astrometric interpretations of photographic plates. The Crimean minor planet service has used his algorithms for a long time.[2] (The honored astronomer should not to be confused with Soviet army General Jānis Balodis.) Naming citation was published on 12 September 1992 (M.P.C. 20837).[8]
References
- ^ a b c d e "JPL Small-Body Database Browser: 4391 Balodis (1977 QW2)" (2016-04-02 last obs.). Jet Propulsion Laboratory. Retrieved 2 May 2016.
- ^ a b Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (4391) Balodis. Springer Berlin Heidelberg. p. 377. ISBN 978-3-540-00238-3. Retrieved 2 May 2016.
- ^ a b c d e f g "LCDB Data for (4391) Balodis". Asteroid Lightcurve Database (LCDB). Retrieved 2 May 2016.
- ^ 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 2 May 2016.
- ^ a b Carbognani, Albino (January 2011). "Lightcurves and Periods of Eighteen NEAs and MBAs". The Minor Planet Bulletin. 38 (1): 57–63. Bibcode:2011MPBu...38...57C. ISSN 1052-8091. Retrieved 2 May 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. Retrieved 2 May 2016.
- ^ "4391 Balodis (1977 QW2)". Minor Planet Center. Retrieved 2 May 2016.
- ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 2 May 2016.
External links
- Asteroid Lightcurve Database (LCDB), query form (info)
- 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
- 4391 Balodis at the JPL Small-Body Database
