Stephen Glenwood MacLean, physicist, astronaut (b at Ottawa 14 Dec 1954). MacLean entered the Canadian Astronaut Program in December 1983 after earning his doctorate in physics from York University. He trained as a payload specialist involved in improving the efficiency of the Canadarm, the robotic arm used on the Space Shuttle. MacLean became the third Canadian to fly in space (22 Oct - 1 Nov 1992) aboard the Shuttle Discovery. He tested a new computerized TV system for controlling the operations of the robot arm.