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 by C. Torres
S. Barros
Discovery site Cerro El Roble Stn.
Discovery date1 December 1975
Designations
(2741) Valdivia
Named after
Pedro de Valdivia [2]
(Spanish conquistador)
1975 XG ·1935 CM
1952 DJ2 ·1953 QS
1969 EB1 ·1969 FC
1973 FX1 ·1979 UA1
1990 FO3
main-belt  ·(middle) [3]
Orbital characteristics [1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc 81.74 yr (29,856 days)
Aphelion 3.0836 AU
Perihelion 2.1352 AU
2.6094 AU
Eccentricity 0.1817
4.22 yr (1,540 days)
142.32°
0° 14m 1.68s / day
Inclination 10.287°
151.13°
91.480°
Physical characteristics
9.13±0.43 km [4]
10.73±0.64 km [5]
11.679±0.172 km [6] [7]
17.52 km (calculated) [3]
4.096±0.0005  h [8]
4.096±0.001 h [9]
4.098±0.001 h [10]
8.191±0.0001 h [11]
  • (269.0°, −31.0°) (λ11) [12]
  • (103.0°, −59.0°) (λ22) [12]
0.10 (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]
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]

    Contents

    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 ( U=3 ). [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 ( U=2+ ). [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 ( U=2 ), [8] and French amateur astronomer René Roy obtained a period of 8.1922 hours (twice the period solution) with an amplitude of 0.36 ( U=2 ). [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) ( U=n.a. ). [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 2 3 4 "JPL Small-Body Database Browser: 2741 Valdivia (1975 XG)" (2016-11-23 last obs.). Jet Propulsion Laboratory . Retrieved 18 September 2017.
    2. 1 2 3 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. 1 2 3 4 5 6 "LCDB Data for (2741) Valdivia". Asteroid Lightcurve Database (LCDB). Retrieved 18 September 2017.
    4. 1 2 3 4 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 18 September 2017.
    5. 1 2 3 4 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)
    6. 1 2 3 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 18 September 2017.
    7. 1 2 3 4 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.
    8. 1 2 3 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. arXiv: 1504.04041 . Bibcode:2015AJ....150...75W. doi:10.1088/0004-6256/150/3/75 . Retrieved 18 September 2017.
    9. 1 2 Pray, Donald P. (March 2004). "Lightcurve analysis of asteroids 1225, 1301, 2134, 2741, and 3974" (PDF). Minor Planet Bulletin. 31 (1): 6–8. Bibcode:2004MPBu...31....6P. ISSN   1052-8091 . Retrieved 18 March 2020.
    10. 1 2 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" (PDF). Minor Planet Bulletin. 44 (2): 145–149. Bibcode:2017MPBu...44..145B. ISSN   1052-8091. Archived from the original (PDF) on 22 March 2020. Retrieved 18 March 2020.
    11. 1 2 Behrend, Raoul. "Asteroids and comets rotation curves – (2741) Valdivia". Geneva Observatory . Retrieved 18 September 2017.
    12. 1 2 3 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. arXiv: 1510.07422 . Bibcode:2016A&A...586A.108H. doi:10.1051/0004-6361/201527441. ISSN   0004-6361.
    13. 1 2 "2741 Valdivia (1975 XG)". Minor Planet Center. Retrieved 18 September 2017.
    14. "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 18 September 2017.