Stewart Sharpless (March 29, 1926 – January 19, 2013)[1] was an American astronomer who carried out fundamental work on the structure of the Milky Way galaxy.
[3] In 1952, Sharpless and Osterbrock published their observations that demonstrated the spiral structure of the Milky Way by estimating the distances to H II regions and young hot stars.
[4] For a while Sharpless was at Mount Wilson Observatory where he worked on galaxy photography with Walter Baade and Edwin Hubble.
[5] In 1953 Sharpless joined the staff of the United States Naval Observatory Flagstaff Station.
Stewart Sharpless was before his death a retired Professor Emeritus in the Department of Physics and Astronomy at the University of Rochester.