Asteroids approaching the Earth from directions around the Sun |
| |
Authors: | Syuzo Isobe and Makoto Yoshikawa |
| |
Affiliation: | (1) National Astronomical Observatory, Mitaka, 181 Tokyo, Japan;(2) Communication Research Laboratory, Hirai, Kashima, 314 Ibaraki, Japan |
| |
Abstract: | We have estimated close asteroid encounters with the Earth by numerical integrations of a system with the Sun, 9 planets, and 188 near-earth-asteroids during the period 1994–4600. Asteroids approach the Earth from directions within 30 around the Sun in more than 20% of encounters with the closest distance less than 0.01 AU. Since ground-based observations cannot detect these objects, we should develop space-borne and/or lunar observatories in a short time to allow enough warning time before a catastrophic collision. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|