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Charles Piazzi Smyth

Charles Piazzi Smyth FRSE FRAS FRSSA FRS (3 January 1819 – 21 February 1900) was an English astronomer who was Astronomer Royal for Scotland from 1846 to 1888; he is known for many innovations in astronomy and his pyramidological and metrological studies of the Great Pyramid of Giza.