Discovered by Y. Väisälä MPC designation 1567 Alikoski Discovered 22 April 1941 Orbits Sun Discovery site Iso-Heikkilä Observatory | Discovery date 22 April 1941 Minor planet category main-belt · (outer) Absolute magnitude 9.47 Discoverer Yrjö Väisälä Asteroid group Asteroid belt | |
Named after Heikki Alikoski (astronomer) Alternative names 1941 HN · 1947 HE1947 HG · 1948 OC Similar 1450 Raimonda, Sun, 516 Amherstia, 276 Adelheid, 193 Ambrosia | ||
1567 Alikoski, provisional designation 1941 HN, is a rare-type carbonaceous asteroid from the outer region of the asteroid belt, approximately 67 kilometers in diameter. It was discovered on 22 April 1941, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland.
The dark C-type asteroid is also classified as a rare PU in the Tholen taxonomic scheme. It orbits the Sun at a distance of 2.9–3.5 AU once every 5 years and 9 months (2,100 days). Its orbit has an eccentricity of 0.08 and an inclination of 17° with respect to the ecliptic. Alikoski's observation arc begins with a precovery taken at Turku in 1938, extending it by 3 years prior to the asteroid's official discovery observation.
In March 2004, a rotational light-curve of Alikoski was obtained by American amateur astronomer Robert D. Stephens at Santana Observatory in California. The light-curve analysis gave a well-defined rotation period of 16.405 hours with a brightness variation of 0.16 magnitude (U=3).
According to the space-based surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Alikoski measures between 62.36 and 77.10 kilometers in diameter, and its surface has a low albedo between 0.04 and 0.062. The Collaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.0626 and a diameter of 67.83 kilometers based on an absolute magnitude of 9.47.
This minor planet was named in honor of Finnish astronomer Heikki Alikoski (1912–1997), assistant to the discoverer from 1937 to 1956, and an observer and discoverer of minor planets himself. He also helped greatly in establishing the Turku Astronomical-Optical Institute. Naming citation was published before November 1977 (M.P.C. 3930).