Back in the 60's, some amateur astronomers observing Venus with a homebuilt telescope and ultraviolet filters discovered that the clouds on Venus had a four-day

Back in the 60's, some amateur astronomers observing Venus with a homebuilt telescope and ultraviolet filters discovered that the clouds on Venus had a four-day rotation period. They submitted their work to a journal of planetary studies, but it was rejected with this comment: "the four-day rotation is theoretically impossible, and shows how foolish the work of the inexperienced amateur can be." In 1974 Mariner 10 few past Venus and confirmed the atmosphere does indeed rotate every four days, much faster than the solid planet beneath. Who was the expert who rejected the very good work of the amateurs? Carl Sagan.