Piet van de Kamp (December 26, 1901 in Kampen – May 18, 1995 in Amsterdam), known as Peter van de Kamp in the United States, was a Dutch astronomer who lived in the United States most of his life. He was professor of astronomy at Swarthmore College and director of the college's Sproul Observatory from 1937 until 1972. He specialized in astrometry, studying parallax and proper motions of stars. He came to public attention in the 1960s when he announced that Barnard's star had a planetary system based on observed "wobbles" in of its motion, but this is now known to be false.