1449 Virtanen, provisional designation 1938 DO, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 9.2 kilometers in diameter. It was discovered on 20 February 1938, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland,[15] and named for Finnish biochemist Artturi Virtanen.[2]

1449 Virtanen
Shape of Virtanen modelled from its lightcurve
Discovery[1]
Discovered byY. Väisälä
Discovery siteTurku Obs.
Discovery date20 February 1938
Designations
(1449) Virtanen
Named after
Artturi Virtanen (biochemist)[2]
1938 DO · 1928 DC
main-belt · Flora[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc89.10 yr (32,543 days)
Aphelion2.5378 AU
Perihelion1.9069 AU
2.2223 AU
Eccentricity0.1419
3.31 yr (1,210 days)
289.08°
0° 17m 51s / day
Inclination6.6413°
110.78°
132.16°
Physical characteristics
Dimensions9.15±1.91 km[4]
9.263±0.098 km[5]
9.46±0.33 km[6]
9.947±0.092 km[7]
10.31 km (calculated)[3]
14.770±0.440 h (R)[8]
30.495±0.005 h[9]
30.5±0.5 h[10]
30.5005±0.0005 h[11]
30.5006±0.0001 h[12]
30.52±0.01 h[10]
30.5421±0.7655 h (R)[13]
30.5465±0.3727 h (S)[13]
0.24 (assumed)[3]
0.285±0.038[6]
0.2856±0.0274[7]
0.36±0.15[4]
Tholen = S[1] · S[3]
11.690±0.150 (R)[8] · 11.779±0.003 (R)[13] · 12.0[7] · 12.1[1][3][6] · 12.25[4] · 12.615±0.004 (S)[13] · 13.21±0.09[14]

Description

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Virtanen is a member of the Flora family, one of the largest collisional populations of stony asteroids in the main-belt. It orbits the Sun in the inner main-belt at a distance of 1.9–2.5 AU once every 3 years and 4 months (1,210 days). Its orbit has an eccentricity of 0.14 and an inclination of 7° with respect to the ecliptic.[1] In 1928, Virtanen was first identified as 1928 DC at Heidelberg, extending the body's observation arc by 10 years prior to its official discovery at Turku.[15]

Physical characteristics

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In the Tholen taxonomy, Virtanen is classified as a common S-type asteroid.[1]

Lightcurves

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Virtanen's first rotational lightcurve was obtained by astronomers Pierre Antonini and Silvano Casulli in May 2007, followed by Australian astronomer Julian Oey at Leura (E17) and Kingsgrove Observatory (E19) in June 2008. The lightcurves gave a rotation period of approximately 30.5 hours with a brightness variation of 0.6 magnitude (U=2-/3-/3-).[9][10]

Additional periods were obtained from photometric observation in the R and S-band at the Palomar Transient Factory (U=2/2/2),[8][13] and from modeled data using the Lowell photometric database and other data sources, which also gave two spin axis of (307.0°, 58.0°) and (89.0°, 61.0°) in ecliptic coordinates, respectively (U=n.a.).[11][12]

Diameter and albedo

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According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Virtanen measures between 9.15 and 9.947 kilometers in diameter, and its surface has an albedo between 0.285 and 0.36.[4][5][6][7]

The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.24 – derived from 8 Flora, the largest member and namesake of its family – and calculates a diameter of 10.31 kilometers with an absolute magnitude of 12.1.[3]

Naming

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This minor planet was named for famous Finnish biochemist Artturi Virtanen (1895–1973), recipient of the 1945 Nobel Prize in Chemistry and president of the Academy of Finland for many years.[2] The official naming citation was published by the Minor Planet Center on 15 February 1970 (M.P.C. 3023).[16]

References

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  1. ^ a b c d e f "JPL Small-Body Database Browser: 1449 Virtanen (1938 DO)" (2017-03-31 last obs.). Jet Propulsion Laboratory. Retrieved 25 July 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(1449) Virtanen". Dictionary of Minor Planet Names – (1449) Virtanen. Springer Berlin Heidelberg. p. 116. doi:10.1007/978-3-540-29925-7_1450. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f "LCDB Data for (1449) Virtanen". Asteroid Lightcurve Database (LCDB). Retrieved 4 January 2017.
  4. ^ a b c d 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. arXiv:1606.08923. Bibcode:2016AJ....152...63N. doi:10.3847/0004-6256/152/3/63.
  5. ^ a b 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. Retrieved 4 January 2017.
  6. ^ 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. S2CID 46350317. Retrieved 4 January 2017.
  7. ^ 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.
  8. ^ a b c Chang, Chan-Kao; Ip, Wing-Huen; Lin, Hsing-Wen; Cheng, Yu-Chi; Ngeow, Chow-Choong; Yang, Ting-Chang; et al. (August 2015). "Asteroid Spin-rate Study Using the Intermediate Palomar Transient Factory". The Astrophysical Journal Supplement Series. 219 (2): 19. arXiv:1506.08493. Bibcode:2015ApJS..219...27C. doi:10.1088/0067-0049/219/2/27. S2CID 17093124. Retrieved 4 January 2017.
  9. ^ a b Oey, Julian (October 2009). "Lightcurve Analysis of Asteroids from Leura and Kingsgrove Observatory in the Second Half of 2008". The Minor Planet Bulletin. 36 (4): 162–164. Bibcode:2009MPBu...36..162O. ISSN 1052-8091. Retrieved 4 January 2017.
  10. ^ a b c Behrend, Raoul. "Asteroids and comets rotation curves – (1449) Virtanen". Geneva Observatory. Retrieved 4 January 2017.
  11. ^ a b Hanus, J.; Durech, 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: 24. arXiv:1510.07422. Bibcode:2016A&A...586A.108H. doi:10.1051/0004-6361/201527441. S2CID 119112278.
  12. ^ a b 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. Retrieved 4 January 2017.
  13. ^ a b c d e 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. S2CID 8342929. Retrieved 4 January 2017.
  14. ^ 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. S2CID 53493339. Retrieved 4 January 2017.
  15. ^ a b "1449 Virtanen (1938 DO)". Minor Planet Center. Retrieved 4 January 2017.
  16. ^ Schmadel, Lutz D. (2009). "Appendix – Publication Dates of the MPCs". Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008). Springer Berlin Heidelberg. p. 221. Bibcode:2009dmpn.book.....S. doi:10.1007/978-3-642-01965-4. ISBN 978-3-642-01964-7.
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