AI discovers novel trajectory to Alpha Centauri as new physics lab launches with $58M

The mission, currently funded by individual private donors, is expected to cost just $15 million. The spacecraft will carry a cargo weighing at least 1 kilogram, including artistic and scientific payloads, messages, and a copy of the Golden Record, the gold-plated disc of Earth's sounds and images that NASA attached to its two Voyager probes in 1977.

Engineering such a journey is extremely difficult. Alpha Centauri is about 25 trillion miles from Earth. Voyager 1, one of the fastest objects ever launched, has been flying since 1977 and has covered less than 1 percent of that distance; at its speed, the trip would take more than 70,000 years. The Fermi team, led by cofounder and president Philip Johnston, spent a year trying to find a route for a small, solar-powered spacecraft costing only $15 million, struggling with how to provide enough power without making the probe too heavy and fuel-guzzling.

Johnston mentioned the problem on a podcast hosted by Alex Wissner-Gross, a physicist who cofounded PSI, and Wissner-Gross offered to run it through an AI system called Get Physics Done. The open-source software takes a physics research question, breaks it into smaller tasks, and decides which simulations to run, using AI models including Anthropic's Claude or OpenAI's GPT models. A week later, the system produced a novel trajectory, combining well-known orbital maneuvers in a way the Fermi team had not considered, according to a paper that has not been peer reviewed.

The trajectory suggests the spacecraft first slow down so its orbit swings in close to the sun, closer than Mercury. On each close pass, it would fire its engine so that the solar panels get four times the light, and a burst of thrust delivered at high speed would buy more energy than the same burst anywhere else. Because the engine runs only near the sun, the solar panels can stay small and the spacecraft stays light.

Matt Pines, cofounder and CEO of PSI, said the system conducted the research mostly on its own for three days, running on one billion tokens. An astrophysicist on PSI's staff steered it to follow the mission's requirements, asked for a cost analysis and clearer charts, and checked the output for errors. "The fact that it came up with an entirely different mission profile, one that was creative and not one [the Fermi team] had considered—that was the more surprising aspect," Pines said. He cautioned that the model lacks a human researcher's judgment and taste, with no reliable sense of which problems are interesting or approaches worth pursuing, so it often gets stuck chasing dead ends. "I don't think we've yet figured out how these models can internally represent something like that [research taste]," he said.

The project recalls the 2016 Breakthrough Starshot initiative by billionaire tech investor Yuri Milner, who pledged $100 million toward a proof of concept for laser-propelled probes that would reach Alpha Centauri within 20 years; a decade later, nothing has launched. "We didn't want to do another Breakthrough Starshot," Johnston said. "We're dead set on something actually launching." He said the team is not constraining itself to completing the journey within a human lifetime. He also acknowledged the craft would probably not be the first to arrive at Alpha Centauri. If an engine a thousand years from now is even 20 percent faster than today's, a spacecraft launched then would still beat the Fermi probe to Alpha Centauri by more than 10,000 years.

The project is also a quest to answer one of physics's oldest open questions, first posed by the physicist Enrico Fermi in 1950.