El Segundo, Calif.-based Raytheon Space and Airborne Systems, a provider of sensor systems to the US military, has announced that William Hart has assumed leadership of the space business of Raytheon Co. Hart, who joined Raytheon in 1975, succeeds Brian Arnold, who has been named vice president for space strategy. In his new role, Hart will manage Space Systems’ Div.’s suite of programs, establishing plans and strategies, setting the vision and direction of the organization, and leading change management efforts. He previously was a program management executive for the company’s Integrated Defense Systems business. Arnold, a retired lieutenant general, is a former commander of the Space and Missile Systems Center at Los Angeles Air Force Base. In that role, he managed research, design, development, acquisition and sustainment of space launch, command and control, missile and satellite systems. He now will be responsible for understanding the future customer needs and providing viable solutions. He will drive the development of plans to expand core markets, working closely with customers and the scientific community. Raytheon Space and Airborne Systems is part of Raytheon Co. of Waltham, Mass.