Discovered by L. Kohoutek MPC designation 1995 Hajek Minor planet category main-belt · (middle) Discovered 26 October 1971 Discovery site Hamburg Observatory | Discovery date 26 October 1971 Alternative names 1971 UP1 · 1941 EA Observation arc 75.64 yr (27,628 days) Orbits Sun Asteroid group Asteroid belt | |
Similar Sun, 218 Bianca, 216 Kleopatra, 45 Eugenia, Comet Kohoutek | ||
1995 Hajek, provisional designation 1971 UP1, is a metallic asteroid from the middle region of the asteroid belt, approximately 13 kilometers in diameter. It was discovered on 26 October 1971, by Czech astronomer Luboš Kohoutek at the Bergedorf Observatory in Hamburg, Germany.
The asteroid orbits the Sun at a distance of 2.4–2.7 AU once every 4.02 years (1,469 days). Its orbit has an eccentricity of 0.05 and an inclination of 11° with respect to the ecliptic. Measurements of its spectral properties identified it as a metallic X-type asteroid. According to NASA's Wide-field Infrared Survey Explorer (WISE), Hajek is classified as a dark P-type asteroid.
According to the surveys carried out by the Japanese Akari satellite and the WISE with its subsequent NEOWISE mission, the asteroid measures between 12.7 and 15.3 kilometers in diameter and its surface has an albedo of 0.040 and 0.083. The Collaborative Asteroid Lightcurve Link strongly disagrees with the space-based observations and assumes a standard albedo for stony asteroids of 0.200 and calculates a much smaller diameter of 6.5 kilometers. These contrasting albedo and diameter figures closely correspond to a generic magnitude-to-diameter conversion, where, for an absolute magnitude of 13.3, the body's diameter is in the range of 6 to 14 kilometers, based on an albedo between 0.05 and 0.25.
The first rotational light-curve obtained by French amateur astronomers Alain Klotz, Marc Rieugné, and Pierre Thierry in October 2013. It gave a provisional rotation period of 10 hours with a brightness variation of 0.10 magnitude (U=1+).
The minor planet is named after the Bohemian astronomer Tadeáš Hájek (1525–1600), better known by his Latinized name, Thaddaeus Hagecius. He was one of the founders of modern stellar and cometary astronomy, who studied the Great Comet of 1577 and the supernova SN 1572, also known as Tycho's Nova. The lunar crater Hagecius is also named in his honour. Naming citation was published before November 1977 (M.P.C. 4358).