5176 Yoichi
5176 Yoichi is a background asteroid from the central regions of the asteroid belt, approximately in diameter. It was discovered on 4 January 1989 by Japanese astronomers Seiji Ueda and Hiroshi Kaneda at the Kushiro Observatory on Hokkaido, Japan. The likely elongated asteroid has a brightness variation of 0.45 magnitude and occulted a star in the constellation Cetus in November 2014. It was named for the Japanese town of Yoichi.
Orbit and classification
Yoichi is a non-family asteroid from the main belt's background population. It orbits the Sun in the central main-belt at a distance of 1.9–3.5 AU once every 4 years and 5 months. Its orbit has an eccentricity of 0.31 and an inclination of 8° concerning the ecliptic.The body's observation arc begins with its first observations as at Johannesburg Observatory in December 1935, or 53 years before its official discovery observation at Kushiro.
Physical characteristics
Yoichi is an assumed S-type asteroid, while the body's albedo indicates a carbonaceous C-type asteroid .Rotation period
In November 2015, astronomers took photometric data of Yoichi at the Oakley Southern Sky Observatory in Australia. However, no rotational lightcurve could be constructed. The asteroid's brightness amplitude was 0.42 magnitude, indicative of an elongated shape. As of 2018, the body's rotation period, pole, and shape remain unknown.Diameter and albedo
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Yoichi measures between 15.68 and 19.49 kilometers in diameter, and its surface has an albedo between 0.05 and 0.0849.The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0777 and a diameter of 16.54 kilometers based on an absolute magnitude of 12.3.