Main Engine Cut Off

He said that analysis will include how the proposed Deep Space Gateway, a human-tended outpost in cislunar space, could support missions to the lunar surface. “It can enable robotic missions that way initially, and then human return,” he said. “Or, do you pivot and just do human return directly?”

He cautioned that a direct return to the moon might not be sustainable in the long run. “It could be achievable, but you would gut a lot of things in the process to go do that very rapidly,” he said.

To support this scaled back mission profile, the current edition of the Service Module for the Orion (built by the Europeans) is smaller than the previous edition under Constellation. Unfortunately, that also means that the Orion can get into (but cannot then get out of) low lunar orbit, taking from Orion what little value it had for a possible lunar mission.

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But can Orion be repurposed? In contrast to most informed opinion, I believe that of the three major human spaceflight pieces described here, Orion is the one that is the least useful and most likely to vanish. This should not be too surprising, considering that it is an orphaned, smaller piece of a larger system designed to return people to the Moon. Yet work continues on Orion, heedless of any possible change in mission – and has done so throughout the last 8 years as its mission gradually morphed from Moon-Mars spacecraft, to an asteroid spacecraft, to a “Space Station in Deep Space” spacecraft. This bureaucratic resilience suggests that setting Orion aside is a nonstarter – contractors and Congressional advocates may insist on its continuation, in a manner similar to the SLS “lobby,” which assured continuity of that development program.