MacTutor
13th January
On this day in 1865, Henry Perigal debated with John Couch Adams at the Astronomical Club about whether the moon rotates. Perigal wrote in his diary:
Dined with the Astronomical Club; after dinner, the question as to the moon's rotation was put to the vote, when the numbers were: 10 for Adams and rotation, 11 for Perigal and non-rotation.