NASA’s In-Space Propulsion Facility (ISP), formerly known as the Spacecraft Propulsion Research Facility (B–2), is the world’s only facility capable of testing full-scale upper-stage launch vehicles and rocket engines under simulated space conditions and also conducting altitude hot fire. The engine or vehicle can be exposed for indefinite periods to low ambient pressures, low-background temperatures, and dynamic solar heating, simulating the environment the hardware will encounter during orbital or interplanetary travel.
