The consensus problem

The success of Artemis II firmly entrenched the Moon as the central focus for the United States’ human spaceflight program. Mars, which briefly captured the attention of the president last year, has once again faded into the background. The billion dollars NASA requested for a rapid humans-to-Mars program was met with polite indifference from Congress, which never so much as acknowledged the request in its final appropriations legislation. A presidential executive order in December put any uncertainty to rest: The United States shall land humans on the Moon by 2028 and begin the initial build-out of a permanent lunar base by 2030. 

The policy whiplash of the Moon to Mars to the Moon in the space of a single year, while unusual for its speed, was nonetheless a familiar dance for longtime observers of human exploration policy. For decades after Apollo, the Moon and Mars have taken turns enjoying the rhetorical attention of various presidents, but real money only started flowing after the end of the Space Shuttle, when the Space Launch System (SLS) rocket program was written into law in 2011 and paired with the vestigial Orion program.

Fifteen years and more than $100 billion in inflation-adjusted dollars later, Artemis is now showing real results but is still at least two years away from the first Moon landing attempt. What the United States and its international partners will actually do on the lunar surface remains unclear, certainly to the broad public, who has been largely relegated to the sidelines of these deliberations over the past year. 

The latest shift came in late February when NASA administrator Jared Isaacman, prodded by a presidential directive, outlined a complete restructuring of the Artemis program, changing flight dates and missions objectives for Artemis III through V, all to take place before the end of 2028 at the earliest. What we do on the Moon beyond then remains unclear — plans may change again. The money continues to flow nonetheless, and NASA’s human exploration program has hit funding highs not seen in decades. 

NASA’s space science program, in contrast, is a model of consistency. Each of the five major space science divisions is guided by a once-per-decade set of priorities provided by the National Academies of Sciences through a deliberative, consensus-based process. Ask a planetary scientist about the top-priority mission in their field, and they will respond with sample return from Mars. An astrophysicist? Habitable Worlds Observatory. The answers would be the same no matter who was president or whether China was making a play for the Moon.

Why, then, does space science struggle to secure funding? In the best of times, NASA’s science program rarely exceeds a third of the agency’s annual budget. Within the last year, it faced near extinction with draconian cuts proposed by the White House. And why does human spaceflight struggle to secure stable policy goals but still enjoys the majority of NASA’s funding? 

To answer this, we need to examine an extrinsic, structural distinction in the forces that drive consensus in human and scientific exploration activities as well as the shifts in parochial politics that have dominated funding debates in the United States since the end of Apollo. 

Reaching consensus between two people can be difficult. To reach it among thousands or tens of thousands often requires an external force to drive a variety of viewpoints toward a single outcome. For space science, this force is the objective reality of the Cosmos that the activity aims to understand. Get hundreds of scientists together in a single room and eventually, they will identify the most immediate questions that need focus, the theories that need reinforcement or testing, and the potential benefits to the wider field. The desire to understand reality independent of culture is the consensus-making mechanism that enables the decadal survey process to succeed time after time. Nature itself acts as an external tiebreaker. Open any decadal report and you will find the most important questions that the scientific community wants to answer; the missions themselves are the tools to achieve that. 

But science, as organized in the United States, is distributed and largely implemented via academic and private research institutions that receive individual grants for specific work. Robotic spacecraft became the specialty of two NASA centers and cost far less than their human-occupied counterparts. Being cheaper, they employ fewer people. This dilutes the political impact of these activities.

Human spaceflight has no consensus driver. The Moon, Mars, low Earth orbit, an asteroid — all priorities are functionally a product of opinion, however passionate. There is no objective reason why one should be the goal over any other. Engineering and cost serve as the primary constraints on near-term human exploration goals. But nothing anchors horizon goals, so they tend to drift. 

What human spaceflight lacks in long-term consensus is made up for in political strength. It is no easy feat to launch a human and a small bubble of Earth’s atmosphere into the unforgiving environment of space. These costs and large support workforces are concentrated at several NASA centers and major contractors, some of which have worked on the same multibillion-dollar contracts for decades. 

Furthermore, due to random accidents of history, the NASA centers that specialize in science and those that specialize primarily in human spaceflight are both geographically and politically distinct. The extensive testing, training, and operations facilities necessary for Project Apollo spurred infrastructure build-outs almost entirely located in the southern United States — a product of a domestic southern-state investment initiative and the southern Democratic senators who controlled key committees within Congress in the 1960s. The political transformation of the South over the subsequent 50 years made the political representation of these centers, located in Alabama, Florida, Texas, and Louisiana, overwhelmingly Republican. The states hosting NASA’s science centers, California and Maryland, went in the opposite direction and became much more Democratic. 

So, while partisanship (at least at the congressional level) remains largely absent from human exploration and space science programs, the parochial political interests of both activities now fall along party lines. 

This, then, can explain the surges of funding for human spaceflight, particularly in the past year under unified Republican control of Congress and the White House. Even in years when the politics are inverted, the concentrated quality of the human exploration program’s workforce and spending makes it politically stronger. Science, more distributed and currently represented by members of the minority party, lacks the concentrated political force needed to protect its funding in lean times. 

Space exploration, ultimately, is a human endeavor. Despite its idealism, it is a product of politics, with all of the messiness and motivations that this entails. With the Artemis program, we are moving into a period of potential alignment between human spaceflight’s goals and near-term achievements. At the same time, the near-death experience of space science in 2025 created a bipartisan coalition of support in Congress rarely seen in modern politics. Perhaps a fusion is the path forward: a tighter integration of science into Artemis that provides helpful constraints on the future of the program and increases the parochial salience of space science itself.