1999 Hirayama is an asteroid discovered by Luboš Kohoutek at Bergedorf in 1973. It is named after Kiyotsugu Hirayama the Japanese astronomer best known for his discovery that many asteroid orbits were more similar to one another than chance would allow leading to the concept of asteroid families now called Hirayama families.The light curve of 1999 Hirayama shows a periodicity of 15.63 ± 0.01 hours during which time the brightness of the object varies by 0.45 ± 0.04 in magnitude.
This page contains content from the copyrighted Wikipedia article "1999 Hirayama"; that content is used under the GNU Free Documentation License (GFDL). You may redistribute it, verbatim or modified, providing that you comply with the terms of the GFDL.