12-Year-Old Builds Nuclear Fusion Reactor That Detects Genuine Neutrons

Starting at just eight years old, Aiden McMillan developed a keen fascination with nuclear physics — driven purely by curiosity rather than academics.

For two years, he focused on absorbing theoretical knowledge without touching any physical equipment. Only after this foundation did he begin constructing his device.

By age 12, through efforts in a spare bedroom and a nonprofit workshop in West Dallas, this seventh-grader managed to assemble a machine that achieved nuclear fusion, positioning him as a contender for a Guinness World Record.

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Aiden McMillan shares insights about his fusion project. Image credit: NBC 5 News

Speaking to NBC DFW, McMillan explained his motivation: “It doesn’t boost my abilities or speed but, in the bigger picture, I believe fusion represents the future of energy.”

Mastering Theory Before Building

Enrolled in the Dallas Independent School District, McMillan dedicated the project's initial two years to learning the principles of nuclear physics. This step was crucial to converting complex theory into practical engineering.

Following this, he spent another two years crafting and experimenting with his designs. After developing seven different prototypes, overcoming failed parts, scrapped plans, and mastering the operation of vacuum pumps and high-voltage systems beyond typical middle school skills, he reached a working model.

The homemade fusor created by Aiden McMillan at Launchpad Incubator. Image credit: Elías Valverde II / Staff Photographer

“I loved the work but sometimes it was really challenging,” McMillan admitted to NBC DFW.

Most of the construction was carried out at Launchpad, a nonprofit makerspace located in West Dallas that supports innovative student engineering efforts — a place McMillan’s determination helped inspire.

Understanding the Fusor's Mechanics

Nuclear fusion powers the sun by fusing two light atomic nuclei into a heavier nucleus, releasing energy in the process.

McMillan’s device, a fusor, accelerates deuterium atoms (a hydrogen isotope) using high voltage within a sealed chamber until some atoms collide with sufficient speed to fuse. Although it doesn't generate usable energy, its purpose is to prove fusion is occurring.

Evidence of fusion is detected through neutrons, which are emitted as a fusion byproduct. Professionals rely on neutron detection to verify fusion events. According to Newsweek, independent testing has validated McMillan’s neutron detection results.

When the neutron detector registered activity, McMillan’s reaction was emotional: “We got neutrons, yeah! It was overwhelming — like reaching the end of a very long journey,” he told NBC DFW.

Ensuring Safety and Gaining Family Support

Constructing a fusion device at home naturally raised safety concerns, and McMillan’s mother insisted on a full understanding of potential risks before approving the project.

“My mom was worried; she wanted a clear explanation of what could possibly go wrong and assurance it wouldn’t happen,” McMillan explained to NBC DFW.

The pivotal moment occurred when the machine successfully emitted neutrons. Image credit: @Dexerto/X

Her support was critical to the project’s continuation. Instead of avoiding safety issues, the family addressed them thoroughly, enabling the build to move forward.

Chasing the Youngest Fusion Record

The official Guinness World Record for the youngest individual accomplishing nuclear fusion currently belongs to Jackson Oswalt from Memphis, Tennessee. He reached fusion just hours before turning 13 in 2018, following a self-taught journey that began at age 11 in a home playroom turned lab, utilizing parts sourced online. Verification of his results came from the Open Source Fusor Research Consortium, with Guinness recognition awarded in October 2020.

Previously, Oswalt surpassed the record set by Taylor Wilson who accomplished fusion at 14 in 2008.

Following Oswalt’s discovery, FBI agents visited his home to scan for radiation, finding no hazardous levels.

At 12, McMillan’s fusion achievement potentially makes him younger than Oswalt was when he accomplished his results. He has submitted his entry to Guinness World Records and awaits formal assessment.

The Significance of His Work

Like previous young fusion pioneers, McMillan’s fusor doesn’t resolve the challenge of producing fusion-based electricity. While it initiates authentic fusion reactions, it yields no net electrical power. Bridging the gap from demonstration to practical fusion energy remains a primary goal in the field.

Nonetheless, McMillan’s accomplishment is impressive. Over four years, he developed seven prototypes, mastered complex systems, and recorded neutron outputs verified independently. His Guinness application is under review, marking a promising milestone in youth-led science innovation.