The Fermi Explorer Mission, a nonprofit led by Starcloud co-founders, plans to launch a small probe toward Alpha Centauri by 2029. With a budget under $15 million, the spacecraft will use solar electric propulsion to reach the nearest star system in approximately 80,000 years, aiming to prove interstellar travel is possible.
It is a mission designed for a deadline that no living human will ever see. The Fermi Explorer seeks to be the first human-made object to intentionally target another star system, even if it is destined to be the last one to arrive. By launching by 2029, the group intends to spark a new era of interstellar ambition using existing technology rather than waiting for theoretical breakthroughs.
The $15 Million Path to Alpha Centauri
While previous interstellar ambitions have required billions of dollars, the Fermi Explorer is positioning itself as a mission. The group, co-founded by Philip Johnston, Adi Oltean, and Ezra Feilden, claims the entire project—including design and construction—will cost under $15 million. To keep costs low, they plan to piggyback on a commercial rocket, such as those from SpaceX, to reach orbit.
The spacecraft itself is modest: a 10cm cube weighing roughly 1 kilogram. This payload will be housed inside a shielded 4 by 4 by 4 inch box. To fund the venture, the nonprofit is utilizing a crowdfunding model, offering rewards such as website recognition for $10 donations and engraving on the craft for contributions of $100 or more.
Solar Electric Propulsion and the Oberth Maneuver
Unlike the laser-driven nanocrafts proposed by earlier projects, Fermi Explorer relies on a tried-and-tested solar electric propulsion system. The mission design, developed by the AI physics research lab Physical Superintelligence, involves a complex orbital dance to build velocity.
After launch, the probe will spend approximately 12 years orbiting the Sun in an oval path. The team will employ the Oberth maneuver, firing boosters as the craft reaches its closest point to the sun to maximize speed gain. This process will repeat over multiple orbits until the spacecraft reaches escape velocity. Technical assessments suggest the probe will finally leave the solar system by the early 2040s.
Ticking Off the Fermi Great Filters
The mission is as much a philosophical statement as a technical one. Philip Johnston, a mathematician and physicist, designed the mission to address the Fermi paradox—the contradiction between the high probability of extraterrestrial life and the lack of evidence for it. Specifically, the mission targets the Fermi Great Filter
, a theoretical barrier that prevents intelligent life from expanding beyond its home star.
By successfully launching the probe, the group argues they can eliminate two specific filters: the idea that it is physically impossible for a species to leave its nearest stars, and the notion that intelligent species simply choose not to leave. As the group stated on its website, the goal is to tick two possible Fermi Great Filters off the list.
“We hope to be both the first to leave and the last to arrive at Alpha Centauri.”
Philip Johnston, Co-founder and President of Fermi Explorer Mission
Interstellar Precedents and Failures
The Fermi Explorer enters a field defined by extreme distances and high failure rates. For comparison, the only other human-made objects to reach interstellar space are Voyager 1 and 2, which entered that space in 2012 and 2018. However, those missions were not targeted at a specific star system. Voyager 1 travels at roughly 37,844 miles per hour, yet Alpha Centauri remains approximately 25 trillion miles away.
The project also serves as a pragmatic alternative to Breakthrough Starshot, a multi-billion-dollar initiative backed by Yuri Milner. While Starshot aimed to reach the system in just 20 years using light-driven sails, that project collapsed in 2025 without a launch. Fermi Explorer accepts a timeline of 79,800 years to ensure the mission actually leaves the ground.
| Mission | Estimated Cost | Target Arrival | Payload |
|---|---|---|---|
| Voyager 1 (1977) | Not specified | No specific target | Not specified |
| Breakthrough Starshot | Billions (proposed) | ~20 years | Not specified |
| Fermi Explorer (2029) | Under $15 million | ~80,000 years | 1 kg |
The Payload and Next Steps
The mission intends to carry a mix of scientific and artistic contributions. This includes a digitized version of the Voyager Golden Record and messages from children worldwide. To fill the remaining space, the mission will soon open a three-month solicitation period for additional payloads.
The founders, who also run Starcloud—an orbital data center startup valued at $2.3 billion—are operating the nonprofit as a separate entity. While Starcloud focuses on commercial AI infrastructure, the Fermi Explorer is a long-term investment in human inspiration. The next critical milestone for the group is the completion of the funding round and the start of the payload solicitation process as they move toward the 2029 launch window.
