David Gill
Sir David Gill\ (June 12 1843 - January 24 1914) was a Scottish astronomer who spent much of his career at the Cape of Good Hope Observatory in South Africa.Used parallax to determine very accurately the distance to the Sun, and also measured distances to the stars. Perfected the use of the heliometer. A pioneer in the use of astrophotography.
Won the Bruce Medal in 1900.