9991 Anežka

9991 Anežka
Discovery [1]
Discovered by Z. Moravec
Discovery site Kleť Obs.
Discovery date 5 October 1997
Designations
MPC designation 9991 Anezka
Named after
 Anežka Moravcová
(discoverer's family)[2]
1997 TY7 · 1977 DX9
1983 GV1 · 1994 BZ
main-belt · Themis [3]
Orbital characteristics [1]
Epoch 16 February 2017 (JD 2457800.5)
Uncertainty parameter 0
Observation arc 39.12 yr (14,287 days)
Aphelion 3.7046 AU
Perihelion 2.6973 AU
3.2009 AU
Eccentricity 0.1573
5.73 yr (2,092 days)
321.68°
0° 10m 19.56s / day
Inclination 2.1773°
80.615°
115.72°
Physical characteristics
Dimensions 7.92 km (calculated)[3]
12.293±0.294 km[4][5]
4.4692±0.0019 h[6]
0.08 (assumed)[3]
0.097±0.013[4][5]
C [3]
12.7[4] · 13.3[1] · 13.415±0.003 (R)[6] · 13.86[3] · 13.89±0.32[7]

    9991 Anežka, provisional designation 1997 TY7, is a carbonaceous Themistian asteroid from the outer region of the asteroid belt, approximately 10 kilometers in diameter. It was discovered on 5 October 1997, by Czech astronomer Zdeněk Moravec at the South Bohemian Kleť Observatory in the Czech Republic.[8]

    Orbit comparison of 9991 Anežka (blue), inner planets (red) and Jupiter (outermost)

    The dark C-type asteroid is a member of the Themis family, a dynamical family of outer-belt asteroids with nearly coplanar ecliptical orbits. It orbits the Sun at a distance of 2.7–3.7 AU once every 5 years and 9 months (2,092 days). Its orbit has an eccentricity of 0.16 and an inclination of 2° with respect to the ecliptic.[1] The first observation was made at the Japanese Kiso Observatory in 1977, extending the asteroid's observation arc by 20 years prior to its discovery.[8]

    A rotational light-curve for this asteroid was obtained from photometric observations at the Palomar Transient Factory in December 2012. It gave it a rotation period of 4.4692±0.0019 hours with a brightness variation of 0.24 in magnitude (U=2).[6]

    According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the asteroid measures 12.3 kilometers in diameter and its surface has an albedo of 0.097,[4] while the Collaborative Asteroid Lightcurve Link assumes an albedo of 0.08 and calculates a diameter of 7.9 kilometers.[3]

    The minor planet was named after the discoverer's grandmother, Anežka Moravcová (b 1924), on her 75th birthday.[2] Naming citation was published on 4 May 1999 (M.P.C. 34632).[9]

    References

    1. 1 2 3 4 "JPL Small-Body Database Browser: 9991 Anezka (1997 TY7)" (2016-04-02 last obs.). Jet Propulsion Laboratory. Retrieved 4 December 2016.
    2. 1 2 Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (9991) Anežka. Springer Berlin Heidelberg. p. 716. ISBN 978-3-540-00238-3. Retrieved 1 August 2016.
    3. 1 2 3 4 5 6 "LCDB Data for (9991) Anezka". Asteroid Lightcurve Database (LCDB). Retrieved 1 August 2016.
    4. 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:1109.6407Freely accessible. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 1 August 2016.
    5. 1 2 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:1109.4096Freely accessible. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 4 December 2016.
    6. 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:1504.04041Freely accessible. Bibcode:2015AJ....150...75W. doi:10.1088/0004-6256/150/3/75. Retrieved 1 January 2016.
    7. ↑ 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:1506.00762Freely accessible. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 1 August 2016.
    8. 1 2 "9991 Anezka (1997 TY7)". Minor Planet Center. Retrieved 1 August 2016.
    9. ↑ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 1 August 2016.

    External links

    This article is issued from Wikipedia - version of the 12/4/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.