NASA - National Aeronautics and Space Administration

"The science of today is the technology of tomorrow."
-- Edward Teller, 20th century American physicist
Cryogenic propellants -- gasses under normal conditions, chilled to subfreezing temperatures and condensed to form highly combustible liquids -- provide high-energy propulsion solutions critical to future, long-term human exploration missions beyond low-Earth orbit. The challenge is to develop means of storing and transferring these propellants in space for long duration, and preventing temperature fluctuations that contribute to fuel losses due to "boil off."

The Cryogenic Propellant Storage & Transfer (CPST) Project will demonstrate the capability to safely and efficiently store, transfer and measure cryogenic propellants , enabling next-generation flight vehicles to store large quantities of fuel for their journeys of discovery.

Why are cryogenic propellants of benefit to spaceflight? They dramatically increase specific impulse, or the amount of thrust delivered per unit mass of rocket fuel, providing much higher performance than conventional propellants and permitting longer-range, higher-payload missions. As NASA seeks innovative paths for human space exploration of multiple potential destinations such as the moon, asteroids, the Lagrange points -- where the gravitational pull from two celestial bodies cancels each other out, permitting stationary orbit -- and Mars and beyond, the need for high-performance technologies is crucial.

The CPST demonstrations will test and validate key cryogenic capabilities and technologies required for future exploration elements, opening up the architecture for large, cryogenic, in-space propulsion systems. The project mitigates risks for multiple architecture elements and systems, including propulsion systems, thermal management systems and power generation and energy storage systems.

Led by NASA's Glenn Research Center in Cleveland, the project completed technology maturation activities in 2012, and is formulating a mission concept to conduct the demonstrations during 2013.