Astronomer Nicolaus Copernicus recorded his first observation after witnessing a moon eclipse with a distant star.

This observation was important as it started his thinking that the sun was in the center of the cosmos.

On March 9, 1497, together with Novara, Copernicus made his first known astronomical observation: At 11 p.m. both watched as the moon briefly eclipsed a distant star, Aldebaran, an event that cast doubt on Ptolemy’s theory of the distance of the moon from the Earth.

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