1245 Calvinia (prov. designation: 1932 KF) is a stony Koronian asteroid from the outer regions of the asteroid belt, approximately 30 kilometers (19 miles) in diameter. It was discovered on 26 May 1932, by South African astronomer Cyril Jackson at the Union Observatory in Johannesburg.[1] The S-type asteroid is likely elongated and has a rotation period of 4.9 hours.[6] It was named for the city of Calvinia in South Africa.[2]

1245 Calvinia
Shape model of Calvinia from its lightcurve
Discovery[1]
Discovered byC. Jackson
Discovery siteJohannesburg Obs.
Discovery date26 May 1932
Designations
(1245) Calvinia
Named after
Calvinia[2]
(South African city)
1932 KF · 1948 VT
1950 CP · A906 FB
A914 YB · A916 DC
A917 KE
main-belt[1][3] · (outer)
background[4] · Koronis[4][5][6]
Orbital characteristics[3]
Epoch 27 April 2019 (JD 2458600.5)
Uncertainty parameter 0
Observation arc112.59 yr (41,125 d)
Aphelion3.1302 AU
Perihelion2.6536 AU
2.8919 AU
Eccentricity0.0824
4.92 yr (1,796 d)
137.36°
0° 12m 1.44s / day
Inclination2.8936°
151.72°
208.24°
Physical characteristics
Mean diameter
26.84±3.5 km[7]
29.751±0.204 km[8][9]
30.444±0.137 km[10]
30.95±0.78 km[11]
4.8523±0.0001 h[12]
0.214[11]
0.2202[10]
0.221[8][9]
0.2713[7]
Tholen = S[3][6]
B–V = 0.847[4]
U–B = 0.474[4]
9.89[7][8][10][11]
9.9[1][3][6]
10.11±0.03[13]

Orbit and classification edit

According to Zappalà, Mothé-Diniz, as well as Milani and Knežević, Calvinia is a member of the Koronis family (605),[4][5] a very large outer asteroid family with nearly co-planar ecliptical orbits.[14] Interestingly, in one of the most recent and complete synthetic HCM-analysis by Nesvorný, Calvinia is not a Koronian asteroid but belongs to the background population.[4]

It orbits the Sun in the outer main-belt at a distance of 2.7–3.1 AU once every 4 years and 11 months (1,796 days; semi-major axis of 2.89 AU). Its orbit has an eccentricity of 0.08 and an inclination of 3° with respect to the ecliptic.[3] The asteroid was first observed as A906 FB at the Heidelberg Observatory in March 1906. The body's observation arc begins with its official discovery observation at Johannesburg in May 1932.[1]

Naming edit

This minor planet was named after the regional city Calvinia in the Cape Province of South Africa.[2] The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 115).[2]

Physical characteristics edit

In the Tholen classification, Calvinia is a common stony S-type asteroid,[4] which is also the overall spectral type for members of the Koronis family.[14]: 23  In the Barucci taxonomy (1987), it is an S0-type asteroid.[4]

Rotation period edit

In October 2017, a rotational lightcurve of Calvinia was obtained from photometric observations by Romain Montaigut, Christophe Gillier and Arnaud Leroy. Lightcurve analysis gave a rotation period of 4.8523±0.0001 hours with a brightness variation of 0.28 magnitude (U=3).[12]

Other rotational were obtained by (ordered by increasing period determinations ) Brines (4.73 h; Δ0.35 mag; U=3-) in 2016,[15] by Lagerkvist (4.8 h; Δ0.52 mag; U=2) and (4.85 h; Δ0.7 mag; U=2) in 1975 and 1978,[16][17] respectively, by Erikson (4.84 h; U=3) in 1990,[18] by Slivan (4.8512 h; Δ0.37 mag; U=3) in 2002, by Roy (4.85129 h; Δ0.50 mag; U=3-),[12] and by Tedesco (4.855 h; Δ0.63 mag; U=3) in 1979.[6]

A modeled lightcurve using photometric data from the Lowell Photometric Database was published in 2016. It gave a concurring period of 4.85148±0.00001 hours, as well as two spin axes at (52.0°, −51.0°) and (235.0°, −43.0°) in ecliptic coordinates (λ, β).[19]

Diameter and albedo edit

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, Calvinia measures between 26.84 and 30.95 kilometers in diameter and its surface has an albedo between 0.214 and 0.2713.[7][8][9][10][11] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.2689 and a diameter of 26.83 kilometers based on an absolute magnitude of 9.9.[6]

References edit

  1. ^ a b c d e "1245 Calvinia (1932 KF)". Minor Planet Center. Retrieved 15 December 2018.
  2. ^ a b c d Schmadel, Lutz D. (2007). "(1245) Calvinia". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 103. doi:10.1007/978-3-540-29925-7_1246. ISBN 978-3-540-00238-3.
  3. ^ a b c d e "JPL Small-Body Database Browser: 1245 Calvinia (1932 KF)" (2018-10-20 last obs.). Jet Propulsion Laboratory. Retrieved 15 December 2018.
  4. ^ a b c d e f g h "Asteroid 1245 Calvinia". Small Bodies Data Ferret. Retrieved 15 December 2018.
  5. ^ a b "Asteroid (1245) Calvinia – Proper elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 14 December 2018.
  6. ^ a b c d e f "LCDB Data for (1245) Calvinia". Asteroid Lightcurve Database (LCDB). Retrieved 15 December 2018.
  7. ^ 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 – IRAS-A-FPA-3-RDR-IMPS-V6.0: IRAS–A–FPA–3–RDR–IMPS–V6.0. Bibcode:2004PDSS...12.....T. Retrieved 15 December 2018.
  8. ^ a b c d Mainzer, A. K.; Bauer, J. M.; Cutri, R. M.; Grav, T.; Kramer, E. A.; Masiero, J. R.; et al. (June 2016). "NEOWISE Diameters and Albedos V1.0". NASA Planetary Data System: EAR–A–COMPIL–5–NEOWISEDIAM–V1.0. Bibcode:2016PDSS..247.....M. Retrieved 15 December 2018.
  9. ^ a b c 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. arXiv:1406.6645. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121. S2CID 119293330.
  10. ^ a b c d 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. S2CID 35447010. (catalog)
  11. ^ 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)
  12. ^ a b c Behrend, Raoul. "Asteroids and comets rotation curves – (1245) Calvinia". Geneva Observatory. Retrieved 15 December 2018.
  13. ^ 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.
  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. S2CID 119280014.
  15. ^ 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 15 March 2020.
  16. ^ 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.
  17. ^ Lagerkvist, C.-I. (December 1977). "Photographic Photometry of the Asteroids 716 Berkeley and 1245 Calvinia". Astronomy and Astrophysics Supplement. 34: 203. Bibcode:1978A&AS...34..203L.
  18. ^ Erikson, A. (December 1989). "Improvement of Rotation Periods for the Asteroids 12 Victoria, 173 Ino and 1245 Calvinia". Asteroids: 55. Bibcode:1990acm..proc...55E.
  19. ^ Durech, J.; Hanus, J.; Oszkiewicz, D.; Vanco, R. (March 2016). "Asteroid models from the Lowell photometric database". Astronomy and Astrophysics. 587: 6. arXiv:1601.02909. Bibcode:2016A&A...587A..48D. doi:10.1051/0004-6361/201527573. S2CID 118427201.

External links edit