Karl Schwarzschild Observatory
8661 Ratzinger, provisional designation , is an Eoan asteroid from the outer region of the asteroid belt, approximately 13.4 kilometers in diameter. It was discovered on 14 October 1990, by German astronomers Lutz Schmadel and Freimut Börngen at the Karl Schwarzschild Observatory in Tautenburg, eastern Germany. The asteroid was named after Cardinal Joseph Ratzinger, who became Pope Benedict XVI.