Asteroid Observations in the Bisei Spaceguard Center

Abstract

The evolution of the Earth has been much affected by asteroid and comet impacts. As known in the Tunguska impact in 1908, the impacts are also threat for the human civilization. In order to avoid such threat, the discovery and follow-up observations of asteroids and comets, especially near-earth objects (NEO), are necessity. We have been carrying out the observations of NEO in Bisei Spaceguard Center since 2000. We have discovered more than 100 asteroids, and one of which was asteroid 20826, the second largest Apollo-type asteroid. We have also contributed to derivations of accurate orbital elements of known asteroids by follow-up observations. In addition to these discoveries and follow-up observations, the observations for physical properties are also important. For example, we have started light curve observations to determine the rotational period of asteroids. In this paper, we introduce the activities of Bisei Spaceguard Center.