On Tuesday, the International Space Exploration Coordination Group (ISECG), a group of 12 national space agencies that includes NASA, ESA, and Roscosmos, released a revised version of its Global Exploration Roadmap. The document is intended to outline a general strategy for human and robotic exploration over the next few decades, with human missions to the surface of Mars as the long-term goal.
The original version of this document, published in September 2011, offered two scenarios: an “Asteroid Next” approach that sent humans first to near Earth asteroids, then to the Moon and Mars; and a “Moon Next” alternative that sent humans first back to the surface of the Moon, then to asteroids and Mars. The new version offers a single scenario closer to the “Asteroid Next” approach, with humans first going to a captured near Earth asteroid per NASA’s plans as part of its asteroid initiative, with human lunar missions included before crewed missions to Mars in the 2030s. Also included in the mix are “extended duration crew missions” in cislunar space, such as at a Lagrange point.
What is clear is that this roadmap is not intended to establish long-term or permanent presences on asteroids or the Moon, at least by government agencies. The near Earth asteroid aspect of the roadmap includes only two crewed missions to such bodies, at least one to the asteroid NASA seeks to redirect into lunar orbit. (Unlike the 2011 roadmap, the new edition makes no mention of any deep space human missions to near Earth asteroids.) Those crewed missions would come some time in the mid-2020s, after the EM-2 SLS/Orion test mission and perhaps even one of the extended duration crewed missions in cislunar space.
The roadmap sees human missions to the surface of the Moon some time in the late 2020s (about 60 years after Apollo 11), using lunar orbit or a Lagrange point as a staging post for such missions. But those human missons peter out in the early 2030s, and the report makes it clear there is no place n the strategy for an extended human presence on the Moon, at least led by national agencies. “[T]he mission scenario defines a lunar campaign with an ‘exit strategy’ consistent with moving forward with Mars mission readiness,” it states. “However, participating agencies recognize that the fundamental capabilities are available to suport additional missions in the event that lunar science or other exploration activities are identified.”
The expectation of the strategy is that commercial entities will take over activities in some of these areas as the agencies press on to Mars: the roadmap includes roles for commercial or government platforms in low Earth orbit to replace the International Space Station, and “potential commercial opportunities” in both cislunar space and the surface of the Moon (but not, oddly enough, near Earth asteroids, given that companies have recently expressed an interest in prospecting and mining such objects.) The roadmap treats these places less as interesting destinations in their own right than as places to gain experience for human missions to Mars.