Saving space

Engineers take a modern look at proven rocket technologies for the Constellation program.

Just about all of the systems being developed for NASA's Constellation program that will take astronauts back to the moon are beefier than those developed for manned space flight in the 1970s-including a crew capsule that holds twice the number of astronauts and a lunar lander three times the size of the Apollo lander.

That is also true for the many engines being developed for the program-the Ares stage-one and -two rocket engines, the Orion service module engines, and the Altair lunar lander engines.