1029 La Plata

1029 La Plata
Shape model of La Plata from its lightcurve
Discovery[1]
Discovered byJ. F. Hartmann
Discovery siteLa Plata Obs.
Discovery date28 April 1924
Designations
(1029) La Plata
Named after
La Plata[2] (city in Argentina
and discovering observatory)
1924 RK · 1938 DR2
1969 OU · A916 UL
A916 UR
main-belt[1][3] · (outer)
Koronis[4][5]
Orbital characteristics[3]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc100.68 yr (36,772 d)
Aphelion2.9715 AU
Perihelion2.8083 AU
2.8899 AU
Eccentricity0.0282
4.91 yr (1,794 d)
87.729°
0° 12m 2.16s / day
Inclination2.4254°
29.903°
142.56°
Physical characteristics
16.46±1.07 km[6]
19.32±2.72 km[7]
20.71 km (derived)[4]
20.78±1.9 km[8]
14 h[9]
14.174±0.003 h[10]
15.310±0.003 h[11]
15.37 h[12]
0.1655 (derived)[4]
0.1819±0.039[8]
0.229±0.246[7]
0.310±0.045[6]
Tholen = S[3][4] · S[13]
B–V = 0.787[3]
U–B = 0.390[3]
10.79[7] · 10.88[3][6][8]
10.99[4][12]
11.01±0.01[11]
11.37±0.60[13]

1029 La Plata, provisional designation 1924 RK, is a stony Koronis asteroid from the outer regions of the asteroid belt, approximately 20 kilometers (12 miles) in diameter. It was discovered on 28 April 1924, by German astronomer Johannes Hartmann at the La Plata Astronomical Observatory in Argentina.[1] It was named after the city of La Plata, Argentina, where the discovering observatory is located. The possibly elongated S-type asteroid has a rotation period of 15.31 hours.[3]

Orbit and classification

La Plata is a member of the Koronis family (605),[4][5] a prominent asteroid family with nearly co-planar ecliptical orbits and one of the largest families in the main belt at all.[14] It orbits the Sun in the outer asteroid belt at a distance of 2.8–3.0 AU once every 4 years and 11 months (1,794 days; semi-major axis of 2.89 AU), which is near the 5:2 resonance with Jupiter (2.82 AU). Its orbit has an eccentricity of 0.03 and an inclination of 2° with respect to the ecliptic.[3]

The asteroid was first observed as A916 UL and A916 UR at the observatories at Simeiz and Algiers in October 1916, respectively. Its observation arc begins with the latter observation at Algiers on 31 October 1916, more than 7 years prior its official discovery observation at La Plata.[1]

Physical characteristics

In the Tholen classification, La Plata is a common, stony S-type asteroid,[3][4] which agrees with the overall spectral type for Koronian asteroids.[14]: 23  The photometric survey conducted by Pan-STARRS also characterized it as an S-type.[13]

Rotation period

In October 2004, a rotational lightcurve of La Plata was obtained from photometric observations during an extensive survey of Koronian asteroids at seven different observatories in the United States. Lightcurve analysis gave a well-defined rotation period of 15.310 hours with a brightness variation of 0.58 magnitude (U=3).[11] Previous measurements from 1975 and 1983 showed a period of 14 and 15.37 hours, respectively (U=2/2).[9][12] Also in October 2004, an alternative period of 14.174 hours was obtained by French amateur astronomer Laurent Bernasconi (U=2).[10] The consolidated brightness amplitude of 0.26 to 0.58 magnitude indicates that the body's shape is somewhat elongated.[4]

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, La Plata measures between 16.46 and 20.78 kilometers in diameter and its surface has an albedo between 0.1819 and 0.310.[6][7][8] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.1655 and a diameter of 20.71 kilometers based on an absolute magnitude of 10.99.[4]

Naming

This minor planet was named after the city of La Plata, Argentina, where the discovering La Plata Astronomical Observatory is located. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 98).[2]

References

  1. ^ a b c d "1029 La Plata (1924 RK)". Minor Planet Center. Retrieved 19 March 2018.
  2. ^ a b Schmadel, Lutz D. (2007). "(1029) la Plata". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 88. doi:10.1007/978-3-540-29925-7_1030. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f g h i "JPL Small-Body Database Browser: 1029 La Plata (1924 RK)" (2017-07-05 last obs.). Jet Propulsion Laboratory. Retrieved 19 March 2018.
  4. ^ a b c d e f g h i "LCDB Data for (1029) La Plata". Asteroid Lightcurve Database (LCDB). Retrieved 19 March 2018.
  5. ^ a b "Asteroid 1029 La Plata – Nesvorny HCM Asteroid Families V3.0". Small Bodies Data Ferret. Retrieved 24 October 2019.
  6. ^ a b c d 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)
  7. ^ 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 19 March 2018.
  8. ^ a b c d 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. Bibcode:2004PDSS...12.....T. Retrieved 22 October 2019.
  9. ^ a b Lagerkvist, C.-I. (March 1978). "Photographic photometry of 110 main-belt asteroids". Astronomy and Astrophysics Supplement Series. 31: 361–381. Bibcode:1978A&AS...31..361L. Retrieved 19 March 2018.
  10. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1029) La Plata". Geneva Observatory. Retrieved 19 March 2018.
  11. ^ a b c Slivan, Stephen M.; Binzel, Richard P.; Boroumand, Shaida C.; Pan, Margaret W.; Simpson, Christine M.; Tanabe, James T.; et al. (May 2008). "Rotation rates in the Koronis family, complete to H≈11.2". Icarus. 195 (1): 226–276. Bibcode:2008Icar..195..226S. doi:10.1016/j.icarus.2007.11.019. Retrieved 19 March 2018.
  12. ^ a b c Binzel, R. P. (October 1987). "A photoelectric survey of 130 asteroids". Icarus. 72 (1): 135–208. Bibcode:1987Icar...72..135B. doi:10.1016/0019-1035(87)90125-4. ISSN 0019-1035. Retrieved 19 March 2018.
  13. ^ a b c 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 19 March 2018.
  14. ^ a b Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). "Identification and Dynamical Properties of Asteroid Families". Asteroids IV. pp. 297–321. arXiv:1502.01628. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. ISBN 9780816532131.