What are “heritage technologies” and how will NASA leverage those in the transition to the Constellation Program?
Examples of transition technologies are elements of the Apollo-era Saturn V Rockets like the J-2 engine. These kind of technologies will be an integral part of the Areas launch vehicles. As well, Ares will build upon the Space Shuttle elements. For example it will use the shuttle’s solid rocket booster technology and the external tank fabrication facilities.
About the J-2x engine (right) NASA says:
The U.S. launch vehicles that will carry explorers back to the moon will be powered in part by a J–2X engine that draws its heritage from the Apollo-Saturn Program. The new engine, being designed and developed
in support of NASA’s Constellation Program, will power the upper stages of both the Ares I crew launch vehicle and Ares V cargo launch vehicle.
The J–2X builds on the legacy of the Apollo-Saturn Program and relies on nearly a half-century of NASA spaceflight experience, heritage hardware and technological advances.
To learn more about the J-2x Engine download this PDF
Image credit: NASA