4936 Butakov

4936 Butakov, provisional designation, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 5 kilometers in diameter. The asteroid was discovered on 22 October 1985, by Soviet–Ukrainian astronomer Lyudmila Zhuravleva at the Crimean Astrophysical Observatory in Nauchnyj, on the Crimean peninsula. It was named after Russian admiral Grigory Butakov.

Orbit and classification
The S-type asteroid is a member of the Flora family, one of the largest groups of stony asteroids in the main-belt. It orbits the Sun in the inner main-belt at a distance of 2.0–2.6 AU once every 3 years and 5 months (1,254 days). Its orbit has an eccentricity of 0.13 and an inclination of 6° with respect to the ecliptic. The first precovery was obtained at the U.S. Goethe Link Observatory in 1950, extending the asteroid's observation arc by 35 years prior to its discovery.

Rotation period
According to the survey carried out by NEOWISE mission of NASA's space-based Wide-field Infrared Survey Explorer, Butakov measures 4.5 and 4.9 kilometers in diameter and its surface has a high albedo of 0.36 and 0.43, respectively, while the Collaborative Asteroid Lightcurve Link assumes an intermediate albedo of 0.24 – which derives from 8 Flora, the largest member and namesake of this orbital family – and calculates a somewhat larger diameter of 5.4 kilometers.

Diameter and albedo
In 2007, a rotational lightcurves of Butakov was obtained at the Carbuncle Hill Observatory which gave a rotation period of $4.465$ hours with a brightness amplitude of 0.14 in magnitude (U=2). Two more lightcurves were obtained from photometric observations made at the U.S. Palomar Transient Factory in January and February 2014. They showed a rotation period of $4.867$ and $13.828$ hours, respectively, with a corresponding brightness variation of 0.11 and 0.08 in magnitude (U=2/2).

Naming
This minor planet was named in memory of Russian admiral Grigory Butakov (1820–1882), who fought in the Crimean War. In 1856, when the war ended, he became Rear admiral of the Black Sea Fleet and Naval Governor of Nikolaev and Sevastopol. The minor planet 2121 Sevastopol is named after the city on the Crimean peninsula. Butakov is widely credited as being the father of steam-powered ship tactics during the 19th century. The official naming citation was published by the Minor Planet Center on 4 May 1999 (M.P.C. 34620).