Uploaded March 2026 | Updated September 2026, 2 weeks ago

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Date formats and other reasons for Pi Day grumpiness from emeritus astronomy professor Mike Merrifield. More links & stuff in full description below ↓↓↓

More Pi videos from Numberphile: youtube.com/playlist?list=PL4870492ACBDC2E7C

Professor Merrifield on Sixty Symbols (our physics channel): youtube.com/playlist?list=PLcUY9vudNKBNGAgplgACrGL9UlxyDHq7k

Professor Merrifield is also a regular on Deep Sky Videos (our astronomy channel): youtube.com/@DeepSkyVideos

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