At minimum, we would need Moon bases, lunar mining infrastructure, large-scale storage, and a way to launch the dust into space.
No human has even set foot on the Moon in more than 50 years. While China is looking to establish a Moon base by 2028, followed by the U.S. in 2034, a well-functioning mining and dust launching system is likely many decades away.
Another advantage of solar geoengineering is meant to be fine tuning.
Injecting aerosols into the atmosphere can in theory be fine-tuned to reduce negative side effects. Changing where aerosol injections take place, for instance, can drastically change potential side effects and its risk profile.
A giant space cloud offers no such precision.
A law and policy vacuum
To make matters worse, the world currently has little in the way of coherent policy or governance for space and the Moon. Many fundamental questions about human activity in space, such as how to manage the growing layer of bullet-speed space junk orbiting Earth, are unanswered.
Also unanswered is another fundamental question: is Moon mining even legal? Who “owns” space, and the resources in it?
At present, we have a patchwork of contradictory policies.
The 1967 Outer Space Treaty prohibits “appropriation” of space resources (implying a ban on mining), and Article 11.3 of the 1979 Moon Treaty states that the Moon’s resources cannot become property of a country, group or person.
However, the U.S., Russia, and China have not signed the Moon Treaty. In fact, the U.S. has Obama-era legislation, a Trump-era executive order, and a non-binding international agreement — the Artemis Accords — that all emphasize commercial resource extraction.
With such contradictory policy in place, lunar mining is a fundamental legal gray area. Shooting Moon dust off into space is another legal dilemma several steps down the line.
As above, so below
Such a legal patchwork exists because of broader political firewalls.
Similarly to how the 20th-century space race reflected Cold War geopolitics, contemporary space governance is shaped by today’s political rifts. Russia and China have not joined the Artemis Accords, deciding (ironically together) to go it alone. But disagreements over a non-binding agreement are just the tip of the iceberg.
Political disagreements over Moon dust deployment could prove far more dangerous. Different countries could prefer different extents of cooling, or whether Moon dust cooling should be used at all.