Case file · Cosmic event
Gervase of Canterbury's 'split Moon'
On 18 June 1178 five monks at Canterbury told the chronicler Gervase that the upper horn of the new Moon split, and fire, hot coals and sparks sprang out of it.
1178 CE · 51.28, 1.08 · status: disputed
The account
In 1976 the geologist Jack Hartung proposed that the monks had seen the impact that made the lunar crater Giordano Bruno. The idea became famous and is still repeated.
The sceptical view
Later work showed an impact that size would have thrown up a week-long meteor storm on Earth, which no chronicle records. Most astronomers now think the monks saw a meteor lined up with the Moon, or atmospheric shimmer.