Tags: Asteroid.
18161 Koshiishi (provisional designation: 2000 PZ12) is a main-belt minor planet. It was discovered through the BATTeRS survey at the Bisei Spaceguard Center in Bisei Okayama Prefecture Japan on August 7 2000. It is named for Hajime Koshiishi a Japanese astronomer and member of the Japan Spaceguard Association.