Space: Care & Feeding of Rover

To many, the exchanges at the President's news conference last week must have been a bit baffling. A reporter asked about "Project Rover." The President's answer cited "Nerva" and "Rift.'' Despite the lingo, the reply carried considerable significance for the future of U.S. exploration in space.

Project Rover, one of the nation's most ambitious space programs, is designed to build a nuclear-powered rocket engine that could carry man to the moon or beyond. Nerva is the engine itself. Rift the vehicle that Nerva will push. President Kennedy had just returned from a tour of Jackass Flats, 90...