The topic has added resonance right now, given the approaching 50th anniversary of that “giant leap for mankind,” the moment on July 20, 1969, when the American astronaut Neil Armstrong became the first human to set foot on the lunar surface (thereby confirming it wasn’t made of green cheese).

No one has been to the moon since 1972, and space research seems to have faded as a source of fascination for recent generations. Yet a spark of excitement remains. In March, the Trump administration said that it wished to send American astronauts back to the moon in five years, an ambitious timetable not regarded as realistic by more than a few experts.

Private companies are poised to make a giant leap of their own as modern equivalents of the prospectors who flocked to California in the mid-19th century Gold Rush. Like those Forty-Niners, the modern entrepreneurs are convinced there is treasure to be found in them thar heavens, people like Peter Diamandis. He is a co-founder of Planetary Resources, a small company near Seattle that seeks to mine the solar system’s asteroids. “We are on the verge,” Mr. Diamandis said, “of the greatest economic expansion in the history of humanity.”

There are conventions to be observed. A principal agreement is the 1967 Outer Space Treaty, ratified by scores of nations and burdened with the wordy formal title of Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies. It forbids any nation to claim sovereignty over any part of the solar system, and bans weapons of mass destruction in space, with nuclear arms singled out for mention. It is one pact that President Trump, whose dislike of multilateral agreements is well established, has yet to propose that the United States turn its back on.

“What a lot of folks don’t know is that the treaty was actually a disarmament treaty,” Dr. Mirmina told Retro Report. That is true, up to a point. Conventional weapons were conspicuously not outlawed.

Another treaty provision requires nongovernmental entities, a category that presumably includes commercial firms, to have the government’s “authorization and continuing supervision” over their operations. That would appear to appreciably limit businesses’ ability to do as they wish, whether on the moon or deeper in space. But a more recent United States law, the Commercial Space Launch Competitiveness Act of 2015, adopted what looks like a more expansive view by explicitly permitting American companies to gather “space resources.”

A host of legal issues are thus raised, with none of them yet resolved in the courts, as they inevitably must be. On one hand, the 1967 treaty prohibits any national claim to outer space. On the other, the 2015 law gives its blessing to Americans who wish to fly off and harvest galactic resources. “There are some scholars,” Dr. Mirmina said, “who say that the U.S. is not complying with the treaty: If the U.S. can’t appropriate outer space, how can U.S. citizens thereby appropriate outer space?”

Bear in mind, too, that Americans are not the only ones with a stake in a new space race. China, Russia, Japan and Israel, to name a few countries, have their own interests in extraterrestrial exploration. No doubt they would insist on a say in any new international guidelines that may emerge in coming years.

You have to wonder if the next person to step onto the moon ought to be a new Neil Armstrong or a briefcase-toting expert in contract law.

CLYDE HABERMAN, a regular contributor to Retro Report, has been a reporter, columnist and editorial writer for The New York Times, where he spent nearly 13 years based in Tokyo, Rome and Jerusalem. Subscribe to our newsletter here and follow us on Twitter @RetroReport.