Did a medieval flying monk spot Halley's comet, twice? It's complicated

A 11th-century Benedictine monk, Eilmer, attempted flight using wings made of willow wood and cloth, gliding 600 feet before breaking both legs. He reportedly saw Halley's comet in 1066, with some historians suggesting he may have also seen it in 989, though others propose a different comet in 1018. William of Malmesbury documented Eilmer's flight and comet sighting in the 12th century.