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867 Kovacia (prov. designation: A917 DH or 1917 BS) is an elongated, dark asteroid and member of the Hygiea family from the outer regions of the asteroid belt. It was discovered on 25 February 1917, by astronomer Johann Palisa at the Vienna Observatory in Austria.[1] The carbonaceous C/B-type asteroid has a rotation period of 8.7 hours and measures approximately 24 kilometers (15 miles) in diameter. It was named after Austrian physician Friedrich Kovacs (1861–1931).[2]

867 Kovacia
Modelled shape of Kovacia from its lightcurve
Discovery [1]
Discovered byJ. Palisa
Discovery siteVienna Obs.
Discovery date25 February 1917
Designations
(867) Kovacia
Named after
Friedrich Kovacs
(Austrian physician)[2]
A917 DH · 1942 XF
1958 WA · 1917 BS
Orbital characteristics[3]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 0
Observation arc102.93 yr (37,594 d)
Aphelion3.4574 AU
Perihelion2.6751 AU
3.0663 AU
Eccentricity0.1276
5.37 yr (1,961 d)
113.77°
0° 11m 0.96s / day
Inclination5.9738°
46.820°
70.135°
Physical characteristics
  • 24.04±2.2 km[7]
  • 24.113±0.439 km[8]
  • 25.02±0.63 km[9]
Mean density
1.4 g/cm3 (est.)[10]
8.6772±0.0001 h[11]
  • (200.0°, −44.0°) (λ11)[4]
  • (38.0°, −50.0°) (λ22)[4]
  • 0.088±0.005[9]
  • 0.092±0.023[8]
  • 0.0923±0.019[7]
11.5[1][3]

Orbit and classification

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According to Zappalà's classification of dynamical families, and when applying the synthetic hierarchical clustering method (HCM) by Nesvorný, Kovacia is a member of the Hygiea family (601), a very large family of carbonaceous outer-belt asteroids, named after 10 Hygiea, which is the main belt's fourth-largest asteroid.[4][5][14]: 23  However, it is a non-family background asteroid according to another HCM-analysis by Milani and Knežević (AstDys).[6]

It orbits the Sun in the outer asteroid belt at a distance of 2.7–3.5 AU once every 5 years and 4 months (1,961 days; semi-major axis of 3.07 AU). Its orbit has an eccentricity of 0.13 and an inclination of 6° with respect to the ecliptic.[3] The body's observation arc begins at Vienna Observatory on 1 March 1917, or four nights after its official discovery observation.[1]

Naming

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This minor planet was named by Palisa after Friedrich Kovacs (1861–1931), a Vienna physician and internists, who successfully treated and restored the health of the discoverer's wife. The famed Viennese cardiologist also treated Gustav Mahler, who had a defective heart. Kovacs imposed a curtailment of all forms of vigorous exercise, a strict regimen of rest and even the usage of a pedometer to measure the composer's physical effort. These restrictions depressed Mahler and ultimately lead to the Symphony No. 9, his last completed work.[15] The naming was also mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 85).[2]

Physical characteristics

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In the SDSS-based taxonomy, Kovacia is a dark and common carbonaceous C-type asteroid,[12] while in a spectroscopic study of the Hygiea family from 2001, this asteroid has been classified as a somewhat brighter B-type asteroid.[13] The study finds a significant number of objects of this family to belong to this spectral type. Both C/B-types agree with the overall spectral type for the Hygiea family listed by Nesvorný (601).[14]: 23 

Rotation period and poles

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Lightcurve-based 3D-model of Kovacia

In February 2008, a rotational lightcurve of Kovacia was obtained from photometric observations by a collaboration of French and Italian amateur astronomers including René Roy, Silvano Casulli, François Colas, Arnaud Leroy, Federico Manzini, Christophe Demeautis and Jean-François Coliac. Lightcurve analysis gave a well-defined rotation period of 8.6772±0.0001 hours with a high brightness variation of 0.86±0.02 magnitude, indicative of a non-spherical, elongated shape (U=3). The result supersedes a previous observation by Roberto Crippa and Federico Manzini at the Sozzago Astronomical Station (A12) from November 2006, that determined a lower limit of 6 hours (U=1+).[11] Due to observed mutual occultation and eclipsing events, the collaboration of astronomers strongly suspect Kovacia to be a binary asteroid with a satellite orbiting it every 31.9580±0.0005 days.[11] However, no follow-up observations have been published. As of March 2020, this asteroid is neither listed at Johnston's Archive nor has it any kind of binary status in the Lightcurve Data Base.[16][17]

In 2016, a modeled lightcurve gave a concurring sidereal period of 8.67807±0.00002 hours using data from the Uppsala Asteroid Photometric Catalogue, the Palomar Transient Factory survey, and individual observers (such as above), as well as sparse-in-time photometry from the NOFS, the Catalina Sky Survey, and the La Palma surveys (950). The study also determined two spin axes of (200.0°, −44.0°) and (38.0°, −50.0°) in ecliptic coordinates (λ, β).[18]

Diameter and albedo

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According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), and the Japanese Akari satellite, Kovacia measures (24.04±2.2), (24.113±0.439) and (25.02±0.63) kilometers in diameter and its surface has an albedo of (0.0923±0.019), (0.092±0.023) and (0.088±0.005), respectively.[7][8][9] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0772 and a diameter of 23.96 kilometers based on an absolute magnitude of 11.5.[16] Alternative mean-diameter measurements published by the WISE team include (19.808±4.804 km) and (21.049±8.124 km) with corresponding albedos of (0.096±0.067) and (0.093±0.063).[4][16]

References

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  1. ^ a b c d e "867 Kovacia (A917 DH)". Minor Planet Center. Retrieved 4 March 2020.
  2. ^ a b c Schmadel, Lutz D. (2007). "(867) Kovacia". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 79. doi:10.1007/978-3-540-29925-7_868. ISBN 978-3-540-00238-3.
  3. ^ a b c d "JPL Small-Body Database Browser: 867 Kovacia (A917 DH)" (2020-01-31 last obs.). Jet Propulsion Laboratory. Retrieved 4 March 2020.
  4. ^ a b c d e "Asteroid 867 Kovacia – Nesvorny HCM Asteroid Families V3.0". Small Bodies Data Ferret. Retrieved 4 March 2020.
  5. ^ a b Zappala, V.; Bendjoya, Ph.; Cellino, A.; Farinella, P.; Froeschle, C. (1997). "Asteroid Dynamical Families". Planetary Data System: EAR-A-5-DDR-FAMILY-V4.1. Retrieved 4 March 2020.} (PDS main page)
  6. ^ a b "Asteroid 867 Kovacia – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 4 March 2020.
  7. ^ a b c 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 4 March 2020.
  8. ^ a b c 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 4 March 2020.
  9. ^ a b c 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)
  10. ^ Krasinsky, G. A.; Pitjeva, E. V.; Vasilyev, M. V.; Yagudina, E. I. (July 2002). "Hidden Mass in the Asteroid Belt". Icarus. 158 (1): 98–105. Bibcode:2002Icar..158...98K. doi:10.1006/icar.2002.6837. ISSN 0019-1035.
  11. ^ a b c Behrend, Raoul. "Asteroids and comets rotation curves – (867) Kovacia". Geneva Observatory. Retrieved 4 March 2020.
  12. ^ a b Carvano, J. M.; Hasselmann, P. H.; Lazzaro, D.; Mothé-Diniz, T. (February 2010). "SDSS-based taxonomic classification and orbital distribution of main belt asteroids". Astronomy and Astrophysics. 510: 12. Bibcode:2010A&A...510A..43C. doi:10.1051/0004-6361/200913322. Retrieved 4 March 2020. (PDS data set)
  13. ^ a b Mothé-Diniz, Thais; di Martino, Mario; Bendjoya, Philippe; Doressoundiram, Alain; Migliorini, Fabbio (July 2001). "Rotationally Resolved Spectra of 10 Hygiea and a Spectroscopic Study of the Hygiea Family". Icarus. 152 (1): 117–126. Bibcode:2001Icar..152..117M. doi:10.1006/icar.2001.6618. ISSN 0019-1035.
  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.
  15. ^ "Friedrich Kovacs (1861-1931)". mahlerfoundation.org. Retrieved 4 March 2020.
  16. ^ a b c "LCDB Data for (867) Kovacia". Asteroid Lightcurve Database (LCDB). Retrieved 4 March 2020.
  17. ^ Johnston, Wm. Robert (7 February 2020). "Asteroids with Satellites". Johnston's Archive. Retrieved 4 March 2020.
  18. ^ Hanuš, J.; Ďurech, J.; Brož, M.; Marciniak, A.; Warner, B. D.; Pilcher, F.; et al. (March 2013). "Asteroids' physical models from combined dense and sparse photometry and scaling of the YORP effect by the observed obliquity distribution". Astronomy and Astrophysics. 551: A67. arXiv:1301.6943. Bibcode:2013A&A...551A..67H. doi:10.1051/0004-6361/201220701. ISSN 0004-6361.
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