Discovered by Z. Moravec MPC designation 9991 Anezka Discovered 5 October 1997 | Discovery date 5 October 1997 Orbits Sun Asteroid group Asteroid belt | |
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Named after Anežka Moravcová(discoverer's family) Alternative names 1997 TY7 · 1977 DX91983 GV1 · 1994 BZ People also search for Sun, 21290 Vydra, 29402 Obelix | ||
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.
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. 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.
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 7000446920000000000♠4.4692±0.0019 hours with a brightness variation of 0.24 in magnitude (U=2).
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, while the Collaborative Asteroid Lightcurve Link assumes an albedo of 0.08 and calculates a diameter of 7.9 kilometers.
The minor planet was named after the discoverer's grandmother, Anežka Moravcová (b 1924), on her 75th birthday. Naming citation was published on 4 May 1999 (M.P.C. 34632).