HOUSTON — The European Space Agency (ESA) will leverage its International Space Station (ISS) experience with the Automated Transfer Vehicle (ATV) into a critical-path responsibility in the early development of NASA’s Orion/Multi Purpose Crew Vehicle.

ESA will provide a service module for one and possibly two test flights of the new capsule and the new Space Launch System (SLS), the two agencies announced Jan. 16.

The preliminaries, including hardware responsibilities and contractor roles, have been in the works for months. ESA ministers pledged a 60% commitment of their cost — about €450 million ($600 million) in late 2012 — with plans to consider the remaining investment in mid-2014, said Thomas Reiter, ESA’s director of human spaceflight and operations.

The basis of a budding alliance that could place European astronauts aboard future U.S.-led deep space missions to cis-lunar space, near Earth asteroids and perhaps Mars was a longstanding participation in the 15-nation ISS. Specifically, ESA’s pledge to provide five ATV cargo resupply missions to the six-person orbiting space lab will end with a fourth delivery mission this year, followed by a fifth in 2014.

Elements of ATV technology will now be adapted for NASA Exploration Space Mission-1, an unpiloted 2017 test flight of the Orion capsule and the smaller version of the SLS on a flight to the lunar environs, says Bill Gerstenmaier, NASA’s associate administrator for human exploration and operations. Spare service module components developed under the new agreement, if available, could be rededicated to the service module portion of Exploration Space Mission-2, a 2021 piloted test of the Orion and SLS on a similar trajectory.

The two agencies expressed cautious optimism about the future course of the partnership, the first international involvement in NASA’s deep-space ambitions, which are focused on a human mission to a near-Earth asteroid in 2025.

“When we talk about international cooperation, it’s not talked about lightly here,” Gerstenmaier says. “We probably would not have done this without the experience we had on [the] space station. We have learned the real meaning of cooperation is not actually counting on your partner to be there. It’s actually giving up a piece of the spacecraft. That was not done lightly.” “When we talk about cooperation, it’s not just for political reasons,” Reiter adds. “We are looking for synergies in technical and programmatic ways. ESA has proven to be a reliable partner in the context of the ISS. Based on that, especially the ATV, this is a good choice to make for exploration — synergies that have been developed in the past that can be beneficial for reaching a common objective.”

Both agencies were careful not to overcommit. “This is a clear path forward, a clear commitment to a really basic program for the time until the end of this decade,” Reiter says.