1600 Vyssotsky

1600 Vyssotsky, provisional designation, is a rare-type Hungaria asteroid and suspected interloper from the inner regions of the asteroid belt, approximately 7 kilometers in diameter. It was discovered on 22 October 1947, by American astronomer Carl Wirtanen at Lick Observatory in California, United States. It was named after astronomer Alexander Vyssotsky.

Classification and orbit
Vyssotsky is a rare A-type asteroid. Based on its orbital characteristics, it is member of the Hungaria family, that form the last, innermost dense concentration of asteroids in the Solar System. However, due to its rare type, it is a suspected interloper, as Hungarias typically show a different E-type spectra. It orbits the Sun in the inner main-belt at a distance of 1.8–1.9 AU once every 2 years and 6 months (918 days). Its orbit has an eccentricity of 0.04 and an inclination of 21° with respect to the ecliptic. Vyssotsky's observation arc begins with its official discovery observation, as no precoveries were taken, and no prior identifications were made.

Lightcurves
Between 1999 and 2014, several rotational lightcurves of Vyssotsky were obtained by American astronomer Brian D. Warner at his Palmer Divide Observatory, Colorado (see video in ). Light-curve analysis gave a concurring rotation period of 3.201 hours with an averaged brightness variation of 0.18 magnitude (U=2/3/3/3/3/3).

Additional well-defined lightcurves were obtained by astronomers Domenico Licchelli in November 2005 (U=3-), Raymond Poncy, Raoul Behrend, René Roy, Reiner Stoss, Jaime Nomen, Salvador Sanchez also in November 2005 (U=3), David Higgins in May 2007 (U=3), Michael Lucas in November 2010 (U=2+), as well as by Hiromi Hamanowa and Hiroko Hamanowa also in November 2010 (U=3). The most recent photometric observation was made by Robert D. Stephens in September 2015, giving a period of 3.204 hours with an amplitude of 0.24 magnitude (U=3). In spite of its many observations, Vyssotsky's spin axis and spin direction can not be determined with certainty.

Diameter and albedo
According to the surveys carried out by the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Vyssotsky measures between 6.29 and 7.50 kilometers in diameter and its surface has an albedo between 0.321 and 0.547. The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.3 and calculates a diameter of 7.00 kilometers with an absolute magnitude of 12.7.

Naming
This minor planet was named in honor of Russian–American astronomer Alexander Vyssotsky (1888–1973), who joined the faculty of the University of Virginia in 1923 and stayed at the McCormick Observatory on Mount Jefferson, Virginia, for 35 years. He was active in the fields of photometry, astrometry and spectral classification. The official was published by the Minor Planet Center on 20 February 1976 (M.P.C. 3931).