Astronomy:1264 Letaba

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1264 Letaba
Discovery[1]
Discovered byC. Jackson
Discovery siteJohannesburg Obs.
Discovery date21 April 1933
Designations
(1264) Letaba
Named afterLetaba River[2]
(South African river)
1933 HG · 1930 WC
1954 YB · 1962 HJ
1964 VB
Minor planet categorymain-belt · (outer)[3]
background[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc84.54 yr (30,877 days)
|{{{apsis}}}|helion}}3.3108 AU
|{{{apsis}}}|helion}}2.4225 AU
2.8667 AU
Eccentricity0.1549
Orbital period4.85 yr (1,773 days)
Mean anomaly112.30°
Mean motion0° 12m 11.16s / day
Inclination24.953°
Longitude of ascending node235.05°
31.529°
Physical characteristics
Dimensions66.040±0.405 km[5]
67.76±17.00 km[6]
67.79±17.67 km[7]
70.180±23.32 km[8]
70.34±0.77 km[9]
73.629±0.870 km[10]
74.35 km (derived)[3]
74.74±2.1 km[11]
Rotation period12 h[12]
16 h[12]
32.16±0.03 h[13]
32.74±0.02 h (best)[14]
33.27±0.01 h[15]
63.74±0.01 h[16]
Geometric albedo0.0407±0.0432[8]
0.0462 (derived)[3]
0.05±0.07[7]
0.05±0.09[6]
0.0725±0.004[11]
0.0746±0.0114[10]
0.082±0.002[9]
0.093±0.027[5]
SMASS = C[1][3]
Absolute magnitude (H)9.10[9][10][11] · 9.60[3][7] · 9.67[6] · 9.70[1][8] · 9.87±0.22[17]


1264 Letaba, provisional designation 1933 HG, is a carbonaceous asteroid and possible tumbler from the background population of the outer asteroid belt, approximately 70 kilometers in diameter. It was discovered on 21 April 1933, by South African astronomer Cyril Jackson at the Union Observatory in Johannesburg.[18] The asteroid was named for the Letaba River in eastern South Africa.[2]

Orbit and classification

Letaba is a non-family asteroid of the main belt's background population.[4] It orbits the Sun in the outer asteroid belt at a distance of 2.4–3.3 AU once every 4 years and 10 months (1,773 days; semi-major axis of 2.87 AU). Its orbit has an eccentricity of 0.15 and an inclination of 25° with respect to the ecliptic.[1]

The asteroid was first identified as 1930 WC at Simeiz Observatory in November 1930. The body's observation arc begins at Johannesburg, the night before its official discovery observation.[18]

Physical characteristics

In the SMASS classification, Letaba is a carbonaceous C-type asteroid.[1][3]

Rotation period

Several rotational lightcurves of Letaba have been obtained from photometric observations since 2002.[12][13][15][16] The best-rated lightcurve was measured by the Spanish amateur astronomer group OBAS in July 2016. It gave a longer-than average rotation period of 32.74 hours with a brightness variation of 0.28 magnitude ({{{1}}}).[14] It might be a tumbler due to the lightcurve's inconsistent slope segments (T?).[3][16] Based on its current diameter estimate, Letaba would be the second-largest tumbler just behind the Hildian asteroid 1512 Oulu (see List of tumblers).

Diameter and albedo

According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Letaba measures between 66.040 and 74.74 kilometers in diameter and its surface has an albedo between 0.0407 and 0.093.[5][6][7][8][9][10][11]

The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0462 and a diameter of 74.35 kilometers based on an absolute magnitude of 9.6.[3]

Naming

This minor planet was named after the Letaba River, located in eastern South Africa. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 116).[2]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 "JPL Small-Body Database Browser: 1264 Letaba (1933 HG)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2001264. Retrieved 22 November 2017. 
  2. 2.0 2.1 2.2 Schmadel, Lutz D. (2007). "(1264) Letaba". Dictionary of Minor Planet Names – (1264) Letaba. Springer Berlin Heidelberg. p. 105. doi:10.1007/978-3-540-29925-7_1265. ISBN 978-3-540-00238-3. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 "LCDB Data for (1264) Letaba". Asteroid Lightcurve Database (LCDB). http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=1264%7CLetaba. Retrieved 22 November 2017. 
  4. 4.0 4.1 "Asteroid 1264 Letaba – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. https://newton.spacedys.com/astdys/index.php?pc=1.1.6&n=1264. 
  5. 5.0 5.1 5.2 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. doi:10.1088/0004-637X/791/2/121. Bibcode2014ApJ...791..121M. 
  6. 6.0 6.1 6.2 6.3 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. doi:10.3847/0004-6256/152/3/63. Bibcode2016AJ....152...63N. 
  7. 7.0 7.1 7.2 7.3 Nugent, C. R.; Mainzer, A.; Masiero, J.; Bauer, J.; Cutri, R. M.; Grav, T. et al. (December 2015). "NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos". The Astrophysical Journal 814 (2): 13. doi:10.1088/0004-637X/814/2/117. Bibcode2015ApJ...814..117N. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015ApJ...814..117N. Retrieved 22 November 2017. 
  8. 8.0 8.1 8.2 8.3 Masiero, Joseph R.; Nugent, C.; Mainzer, A. K.; Wright, E. L.; Bauer, J. M.; Cutri, R. M. et al. (October 2017). "NEOWISE Reactivation Mission Year Three: Asteroid Diameters and Albedos". The Astronomical Journal 154 (4): 10. doi:10.3847/1538-3881/aa89ec. Bibcode2017AJ....154..168M. 
  9. 9.0 9.1 9.2 9.3 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. doi:10.1093/pasj/63.5.1117. Bibcode2011PASJ...63.1117U.  (online, AcuA catalog p. 153)
  10. 10.0 10.1 10.2 10.3 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. Bibcode2011ApJ...741...90M. 
  11. 11.0 11.1 11.2 11.3 Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System 12: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode2004PDSS...12.....T. https://sbnarchive.psi.edu/pds3/iras/IRAS_A_FPA_3_RDR_IMPS_V6_0/data/diamalb.tab. Retrieved 22 October 2019. 
  12. 12.0 12.1 12.2 Behrend, Raoul. "Asteroids and comets rotation curves – (1264) Letaba". Geneva Observatory. http://obswww.unige.ch/~behrend/page3cou.html#001264. Retrieved 22 November 2017. 
  13. 13.0 13.1 Stephens, Robert D. (December 2002). "Photometry of 430 Hybris, 798 Ruth, 1264 Letaba, and 3786 Yamada". The Minor Planet Bulletin 30 (1): 1–2. ISSN 1052-8091. Bibcode2003MPBu...30....1S. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2003MPBu...30....1S. Retrieved 22 November 2017. 
  14. 14.0 14.1 Brines, Pedro; Lozano, Juan; Rodrigo, Onofre; Fornas, A.; Herrero, David; Mas, Vicente et al. (April 2017). "Sixteen Asteroids Lightcurves at Asteroids Observers (OBAS) - MPPD: 2016 June-November". The Minor Planet Bulletin 44 (2): 145–149. ISSN 1052-8091. Bibcode2017MPBu...44..145B. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2017MPBu...44..145B. Retrieved 22 November 2017. 
  15. 15.0 15.1 Ferrro, Andrea (April 2017). "Rotational Period of Three Main-belt Asteroids". The Minor Planet Bulletin 44 (2): 142. ISSN 1052-8091. Bibcode2017MPBu...44..142F. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2017MPBu...44..142F. Retrieved 22 November 2017. 
  16. 16.0 16.1 16.2 Oey, Julian; Williams, Hasen; Groom, Roger (July 2017). "Lightcurve Analysis of Asteroids from BMO and DRO in 2015". The Minor Planet Bulletin 44 (3): 200–204. ISSN 1052-8091. Bibcode2017MPBu...44..200O. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2017MPBu...44..200O. Retrieved 22 November 2017. 
  17. 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. Bibcode2015Icar..261...34V. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015Icar..261...34V. Retrieved 22 November 2017. 
  18. 18.0 18.1 "1264 Letaba (1933 HG)". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=1264. Retrieved 22 November 2017. 

External links