Sir Robert Stawell Ball FRS (1 July 1840 - 25 November 1913) was an Irish astronomer who founded the screw theory. Ball worked for Lord Rosse from 1865 to 1867. In 1867 he became Professor of Applied Mathematics at the Royal College of Science in Dublin. There he lectured on mechanics and published an elementary account of the science. In 1873 he became a Fellow of the Royal Society. In 1874 Ball was appointed Royal Astronomer of Ireland and Andrews Professor of Astronomy in the University of Dublin at Dunsink Observatory.