Astronomy:2028 Janequeo
| Discovery [1] | |
|---|---|
| Discovered by | C. Torres S. Cofré |
| Discovery site | Cerro El Roble Stn. |
| Discovery date | 18 July 1968 |
| Designations | |
| (2028) Janequeo | |
| Named after | Janequeo (or Yanequén) (Mapuche heroine)[2] |
| 1968 OB1 | |
| Minor planet category | main-belt · Flora [3] |
| Orbital characteristics [1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 47.89 yr (17,491 days) |
| |{{{apsis}}}|helion}} | 2.5550 AU |
| |{{{apsis}}}|helion}} | 2.0382 AU |
| 2.2966 AU | |
| Eccentricity | 0.1125 |
| Orbital period | 3.48 yr (1,271 days) |
| Mean anomaly | 70.128° |
| Mean motion | 0° 16m 59.52s / day |
| Inclination | 7.9558° |
| Longitude of ascending node | 242.80° |
| 27.574° | |
| Physical characteristics | |
| Dimensions | 2.45 km (calculated)[3] 3.201±0.290 km[4][5] |
| Rotation period | 2.480±0.0002 h[6] |
| Geometric albedo | 0.24 (assumed)[3] 0.273±0.070[4][5] |
| S [3] | |
| Absolute magnitude (H) | 14.5[4] · 14.769±0.004 (R)[6] · 14.79±0.38[7] · 14.8[1] · 15.22[3] |
2028 Janequeo, provisional designation 1968 OB1, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 3 kilometers in diameter. It was discovered on July 18, 1968, by Chilean astronomers Carlos Torres and S. Cofre at the Cerro El Roble Station of Chile's National Astronomical Observatory.[8] The asteroid named after the indigenous heroine Janequeo (Yanequén).[2]
Classification and orbit
Janequeo is a member of the Flora family, one of the largest collisional populations of stony asteroids. It orbits the Sun in the inner main-belt at a distance of 2.0–2.6 AU once every 3 years and 6 months (1,271 days). Its orbit has an eccentricity of 0.11 and an inclination of 8° with respect to the ecliptic.[1] The body's observation arc begins at the discovering observatory one night after its official discovery observation on 19 July 1968.[8]
Physical characteristics
Lightcurves
In August 2010, a rotational lightcurve of Janequeo was obtained from photometric observations by astronomers at the Palomar Transient Factory in California. Lightcurve analysis gave a short rotation period of 2.480 hours with a brightness amplitude of 0.27 magnitude ({{{1}}}).[6]
Diameter and albedo
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Janequeo measures 3.201 kilometers in diameter and its surface has an albedo of 0.273.[4][5] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.24 – derived from 8 Flora, the largest member and namesake of the Flora family – and calculates a diameter of 2.45 kilometers based on an absolute magnitude of 15.22.[3]
Naming
This minor planet was named after Janequeo (Yanequén), a heroine and leader of the native Mapuche people of Chile. After her husband Huepotaén died in battle against the colonial Spaniards during the Arauco War in the 16th century, she became tribal chief and brought together various rebellious tribes.[2] The approved naming citation was published by the Minor Planet Center on 1 June 1980 (M.P.C. 5359).[9]
See also
References
- ↑ 1.0 1.1 1.2 1.3 "JPL Small-Body Database Browser: 2028 Janequeo (1968 OB1)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002028.
- ↑ 2.0 2.1 2.2 Schmadel, Lutz D. (2007). "(2028) Janequeo". Dictionary of Minor Planet Names – (2028) Janequeo. Springer Berlin Heidelberg. p. 164. doi:10.1007/978-3-540-29925-7_2029. ISBN 978-3-540-00238-3.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 "LCDB Data for (2028) Janequeo". Asteroid Lightcurve Database (LCDB). http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=2028%7CJanequeo.
- ↑ 4.0 4.1 4.2 4.3 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. doi:10.1088/0004-637X/741/2/90. Bibcode: 2011ApJ...741...90M.
- ↑ 5.0 5.1 5.2 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. doi:10.1088/0004-637X/741/2/68. Bibcode: 2011ApJ...741...68M. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011ApJ...741...68M. Retrieved 29 June 2017.
- ↑ 6.0 6.1 6.2 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. doi:10.1088/0004-6256/150/3/75. Bibcode: 2015AJ....150...75W. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015AJ....150...75W. Retrieved 29 June 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. doi:10.1016/j.icarus.2015.08.007. Bibcode: 2015Icar..261...34V. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015Icar..261...34V. Retrieved 29 June 2017.
- ↑ 8.0 8.1 "2028 Janequeo (1968 OB1)". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=2028.
- ↑ "MPC/MPO/MPS Archive". Minor Planet Center. https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html.
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
- 2028 Janequeo at AstDyS-2, Asteroids—Dynamic Site
- 2028 Janequeo at the JPL Small-Body Database
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