Cislunar Space: The Next 30 Years

Up to speed and thinking about the future, United Launch Alliance (ULA), the amalgam of Boeing and Lockheed created in 2006 to market launch services on the venerable Delta and Atlas rockets, hosted a unique gathering in Centennial, Colorado last week. Approximately 70 invited engineers, scientists and space entrepreneurs gathered at ULA corporate headquarters to consider the pathways and connections of future activities envisioned for cislunar space (the volume of space between and around Earth and the Moon). Working from ULA’s concept of 1000 people working in cislunar space within the next 30 years, we were tasked to consider and work out what these people will do and how the ULA Cislunar 1000 vision will come to pass. (See video and slides from the meeting.)

Those who’ve been following changes within NASA and the growing arena of commercial space have noticed the increasing attention paid to cislunar space. ULA developed Cislunar 1000 because they foresee a wide variety of potential commercial activities in space built around the manufacture and sale of space resources—specifically water and the propellant derived from it to fuel transfer stages that move payloads around and through cislunar space.

Many government and commercial satellites require orbits much higher than the low Earth orbit (LEO) to which most launch vehicles deliver their payloads. Typically, a satellite destined for such a high orbit (e.g., geosynchronous orbit (GEO), the 22,000-mile-high orbit at which one revolution of the Earth takes 24 hours, making the satellite as viewed from Earth appear stationary in the same part of the sky) carries a special boost stage to deliver the spacecraft to GEO. The ULA plan would maintain a fleet of space vehicles designed to deliver these satellites to their high orbits and then return to LEO to be re-fueled and prepared for the next delivery.

Such a system requires a variety of space-based assets, including fueling stations, propellant depots, transfer stages and transit nodes. Key to making this system work is the development and use of extraterrestrial supplies of propellant, i.e., water procured from the Moon’s poles and from asteroids. A resource-processing outpost on the Moon—close, accessible and possessing usable quantities of water in the form of ice—thus becomes a critical part of the ULA development scheme.

Brainstorming at this workshop included discussions on the unknowns of establishing a permanent lunar presence: What must we fully understand before initiating this plan? Although we know that water ice exists at the poles of the Moon, we do not know how it is distributed laterally and vertically on meter-scales, its physical state, and how the ice might be accessed and processed. These prospecting questions could be addressed by flying a series of small robotic missions to obtain strategic information on the location and state of polar ice deposits. Designing the equipment needed to excavate and process this ice is dependent on this knowledge, though we can make some initial educated guesses on what will be required.

The current template for commercial space depends upon expendable launch vehicles delivering disposable satellites, operating for a set period of time, after which they are replaced. Although tentative steps toward satellite servicing, maintenance and life-extension are being investigated, commercial satellite operators cannot move to a paradigm of routine access and servicing until a system to support such a template evolves. To facilitate access to cislunar space, ULA’s plan anticipates a growing commercial market for affordable propellant. Although viewing the federal government as an important potential customer, their long-range vision is not solely dependent upon it. Thus, the ULA scheme involves simultaneously developing both a market demand and a system to supply that demand. Workshop attendees devoted a significant amount of time at the workshop to this problem, which includes determining the intersection of different needs and interests among the various topical fields identified.

Although launch was specifically excluded from consideration (it was assumed that multiple paths to LEO will be available for differing needs), we considered issues and requirements in space transportation, resources, manufacturing, energy and human spaceflight. Each topic was then addressed by two different groups, with the aim of ensuring more complete coverage of all aspects of the problem. Charts showing milestones and estimates of when such milestones might be achieved were drawn up, admittedly an educated guess in many cases. However, upon examination of the various ideas of the different groups, there was a surprising amount of general agreement.

I found this experience useful and educational; it was refreshing to be in a room with 70 individuals who could see that Cislunar 1000 has a reasonable chance of success. For now, much of ULA’s vision remains blue-sky thinking, but this workshop was an encouraging start towards understanding the magnitude of the problems that must be addressed. By embracing this concept and designing an architecture that takes us beyond traditional spaceflight paradigms, we may finally be coalescing behind a long awaited and necessary push against debilitating, risk-adverse thinking.

The ULA Cislunar 1000 vision is in many respects exactly what the Vision for Space Exploration advocated in 2004: To use the material and energy resources of space to create new spacefaring capabilities. Former Presidential Science Advisor John Marburger, to whom tribute was appropriately paid during the opening of the workshop, has most notably advocated this direction. It was gratifying to see Marburger receive credit for his brilliant articulation of one of the most important reasons for opening the space frontier—economic development. And it set the proper tone for the workshop.

Analogous to other commercially built infrastructures here on Earth, the creation of a permanent, interconnecting transportation system in space no longer resides in the realm of science fiction. Last week’s meeting in Colorado is the first industry-supported workshop I have attended that fully appreciated and exploited the leveraging value of space resources to create new capabilities in space. The unsustainable template of selling expensive, custom-built pieces of hardware to launch into space (fashioned to perform for some finite length of time before being replaced) is a roadblock holding us back. To move beyond that approach will require the establishment of a permanent, space-based transportation system.

In conjunction with such a change in the space business model is the perennial battle over “commercial” vs. “government” space. ULA approaches Cislunar 1000 as a commercial venture. Workshop participants did not gather to press for a massive government program to build this system, but rather, to understand how various commercial entities could work together to create it. That said, many in attendance recognize and understand that government has a specific, critical and continuing role to play in the emergence and viability of this new field of commercial endeavor: to serve in its traditional roles as the guarantor of rights and the protector of property rights, as well as spearheading advanced research into technologies suitable for the economic development of space. The legal and regulatory regime of extraterrestrial resource development remains an evolving and uncertain field of legal theory. Other nations have taken an interest in the Moon and cislunar presence (China in particular). Not only U.S. law, but also international agreements and treaty obligations must be considered. Although national security was recognized as an area of significance to be addressed, such considerations were beyond the scope of this meeting.

It was a pleasure attending ULA’s Cislunar 1000 workshop—a productive meeting where diverse ideas were offered and shared by attendees in their sincere, good faith pursuit of a rational and sustainable space development architecture. Regardless of what form the industrialization of cislunar space takes, the foresight of the ULA team that organized this workshop will be remembered for bringing us together to define the problem and to articulate the several possible paths forward.

Paul D. Spudis | READ MORE

Paul D. Spudis (1952-2018) was a senior staff scientist at the Lunar and Planetary Institute in Houston, Texas, and a prolific author on the subject of the moon. His books include The Value of the Moon: How to Explore, Live, and Prosper in Space Using the Moon's Resources.