Astronomy:2741 Valdivia

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2741 Valdivia
002741-asteroid shape model (2741) Valdivia.png
Shape model of Valdivia from its lightcurve
Discovery [1]
Discovered byC. Torres
S. Barros
Discovery siteCerro El Roble Stn.
Discovery date1 December 1975
Designations
(2741) Valdivia
Named afterPedro de Valdivia [2]
(Spanish conquistador)
1975 XG · 1935 CM
1952 DJ2 · 1953 QS
1969 EB1 · 1969 FC
1973 FX1 · 1979 UA1
1990 FO3
Minor planet categorymain-belt · (middle)[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc81.74 yr (29,856 days)
|{{{apsis}}}|helion}}3.0836 AU
|{{{apsis}}}|helion}}2.1352 AU
2.6094 AU
Eccentricity0.1817
Orbital period4.22 yr (1,540 days)
Mean anomaly142.32°
Mean motion0° 14m 1.68s / day
Inclination10.287°
Longitude of ascending node151.13°
91.480°
Physical characteristics
Mean diameter9.13±0.43 km[4]
10.73±0.64 km[5]
11.679±0.172 km[6][7]
17.52 km (calculated)[3]
Rotation period4.096±0.0005 h[8]
4.096±0.001 h[9]
4.098±0.001 h[10]
8.191±0.0001 h[11]
Pole ecliptic latitude
  • (269.0°, −31.0°) (λ11)[12]
  • (103.0°, −59.0°) (λ22)[12]
Geometric albedo0.10 (assumed)[3]
0.205±0.035[6]
0.2052±0.0350[7]
0.244±0.032[5]
0.404±0.066[4]
S/C[3]
Absolute magnitude (H)11.764±0.002 (R)[8] · 11.80[4] · 11.9[1][3] · 12.00[5][7]


2741 Valdivia (prov. designation: 1975 XG) is a background asteroid from the central regions of the asteroid belt, approximately 11 kilometers (6.8 miles) in diameter. It was discovered on 1 December 1975, by Chilean astronomers Carlos Torres and Sergio Barros at the Cerro El Roble Station northwest of Santiago de Chile.[13] The asteroid was named after Spanish conquistador Pedro de Valdivia.[2]

Orbit and classification

Valdivia is a non-family asteroid from the main belt's background population. It orbits the Sun in the central main-belt at a distance of 2.1–3.1 AU once every 4 years and 3 months (1,540 days). Its orbit has an eccentricity of 0.18 and an inclination of 10° with respect to the ecliptic.[1] The asteroid was first observed as 1935 CM at Uccle Observatory in February 1935, where the body's observation arc begins just a two weeks later, or more than 40 years before its official discovery observation at Cerro El Roble.[13]

Naming

This minor planet was named after Spanish conquistador Pedro de Valdivia (1502–1553), who conquered Chile with a small expedition corps after he served under Francisco Pizarro in Peru. Valdivia founded the cities Santiago (1541) and Concepción (1550) and became Chile's first royal governor.[2] The city of Valdivia in southern Chile is also named after him. The official naming citation was published by the Minor Planet Center on 26 March 1986 (M.P.C. 10546).[14]

Physical characteristics

Rotation period

In August 2016, the so-far best-rated rotational lightcurve of Valdivia was obtained by the Spanish amateur astronomer group OBAS. Lightcurve analysis gave a rotation period of 4.098 hours with a brightness variation of 0.25 magnitude ({{{1}}}).[10] Previously, in May 2003, photometric observations made by Donald P. Pray at the Carbuncle Hill Observatory (912) near Providence, Rhode Island, gave a synodic period of 4.096 hours and an amplitude of 0.40 in magnitude ({{{1}}}).[9] In addition astronomers at the Palomar Transient Factory found a period of 4.096 hours with an amplitude of 0.28 om May 2011 ({{{1}}}),[8] and French amateur astronomer René Roy obtained a period of 8.1922 hours (twice the period solution) with an amplitude of 0.36 ({{{1}}}).[11]

Poles

In 2016, an international study modeled a lightcurve with a concurring period of 4.09668±0.00005 hours and found two spin axes of (269.0°, −31.0°) and (103.0°, −59.0°) in ecliptic coordinates (λ, β) ({{{1}}}).[12]

Diameter and albedo

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Valdivia measures between 9.13 and 11.679 kilometers in diameter and its surface has an albedo between 0.205 and 0.404,[4][6][7] while the Japanese Akari satellite found an albedo of 0.244 and a diameter of 10.73 kilometers.[5] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 – a compromise value between the carbonaceous (0.057) and stony (0.20) asteroids – and calculates a diameter of 17.52 kilometers based on an absolute magnitude of 11.9.[3]

References

  1. 1.0 1.1 1.2 1.3 "JPL Small-Body Database Browser: 2741 Valdivia (1975 XG)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002741. 
  2. 2.0 2.1 2.2 Schmadel, Lutz D. (2007). "(2741) Valdivia". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 224. doi:10.1007/978-3-540-29925-7_2742. ISBN 978-3-540-00238-3. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 "LCDB Data for (2741) Valdivia". Asteroid Lightcurve Database (LCDB). http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=2741%7CValdivia. 
  4. 4.0 4.1 4.2 4.3 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. doi:10.1088/2041-8205/759/1/L8. Bibcode2012ApJ...759L...8M. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2012ApJ...759L...8M. Retrieved 18 September 2017. 
  5. 5.0 5.1 5.2 5.3 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)
  6. 6.0 6.1 6.2 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. Bibcode2011ApJ...741...68M. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2011ApJ...741...68M. Retrieved 18 September 2017. 
  7. 7.0 7.1 7.2 7.3 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. 
  8. 8.0 8.1 8.2 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. Bibcode2015AJ....150...75W. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2015AJ....150...75W. Retrieved 18 September 2017. 
  9. 9.0 9.1 Pray, Donald P. (March 2004). "Lightcurve analysis of asteroids 1225, 1301, 2134, 2741, and 3974". Minor Planet Bulletin 31 (1): 6–8. ISSN 1052-8091. Bibcode2004MPBu...31....6P. http://www.minorplanet.info/MPB/issues/MPB_31-1.pdf. Retrieved 18 March 2020. 
  10. 10.0 10.1 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". Minor Planet Bulletin 44 (2): 145–149. ISSN 1052-8091. Bibcode2017MPBu...44..145B. http://www.minorplanet.info/MPB/issues/MPB_44-2.pdf. Retrieved 18 March 2020. 
  11. 11.0 11.1 Behrend, Raoul. "Asteroids and comets rotation curves – (2741) Valdivia". Geneva Observatory. http://obswww.unige.ch/~behrend/page4cou.html#002741. 
  12. 12.0 12.1 12.2 Hanuš, J.; Ďurech, J.; Oszkiewicz, D. A.; Behrend, R.; Carry, B.; Delbo, M. et al. (February 2016). "New and updated convex shape models of asteroids based on optical data from a large collaboration network". Astronomy and Astrophysics 586: A108. doi:10.1051/0004-6361/201527441. ISSN 0004-6361. Bibcode2016A&A...586A.108H. 
  13. 13.0 13.1 "2741 Valdivia (1975 XG)". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=2741. 
  14. "MPC/MPO/MPS Archive". Minor Planet Center. https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html. 

External links