Austin Keith Pierce (October 2, 1918 – March 11, 2005) was an American solar astronomer. Pierce played a key role in the development of the McMath–Pierce solar telescope at Kitt Peak National Observatory in Arizona.

Austin Keith Pierce was born October 2, 1918, in Tacoma, Washington. His father, Tracy Pierce, was a mathematician at the University of Nebraska–Lincoln and an amateur astronomer.^[1][2]

From 1936 to 1938, he studied at the University of Nebraska–Lincoln, before transferring to the University of California, Berkeley where in 1940 he obtained a BSc in astronomy.^[1][2] In 1941 he married Mildred Buell, with whom he went on to have three children.^[1]

During the Second World War, Pierce worked on uranium isotope separation as part of the Manhattan Project, first at the Lawrence Radiation Laboratory and then at Oak Ridge in Tennessee.^[1][2]

In 1945 he returned to Berkeley, obtaining his doctorate in 1948 under C. Donald Shane.^[1][2] He then worked at the University of Michigan for astronomer Robert McMath. McMath obtained federal funding for a large solar telescope and chose Pierce to lead the project.^[3] Pierce gained observing experience at the Mount Wilson and McMath–Hulbert solar observatories and toured European solar observatories to inform the design of the new telescope.^[3]

Kitt Peak Observatory was chosen for the site so in 1958 Pierce and his family relocated to Tucson, Arizona.^[3] Upon completion in 1962 the McMath solar telescope was the largest solar telescope in the world.^[4]

Pierce would direct the solar division of Kitt Peak for 16 years.^[3] In 1979 he married medical anthropologist Trudy Griffin.^[1] In 1992 the McMath telescope was rededicated as the McMath–Pierce Solar Telescope.^[4][5]

Pierce died of cancer on March 11, 2005, in Tucson, Arizona.^[5][6][7]