Charles Piazzi Smyth, Italian-Scottish astronomer and academic (died 1900)

Charles Piazzi Smyth was a British astronomer who was Astronomer Royal for Scotland from 1846 to 1888; he is known for many innovations in astronomy and, along with his wife Jessica Duncan Piazzi Smyth, his pyramidological and metrological studies of the Great Pyramid of Giza.

January 3 is the third day of the year in the Gregorian calendar; 362 days remain until the end of the year.