Nuclear startup
Appears in 1 story · Last updated Aug 8, 2026
As of August 2026: Third company in the pilot program to reach criticality, meeting the federal three-reactor target
On June 4, 2026, Antares Nuclear's Mark-0 reactor at an Idaho desert lab started a self-sustaining nuclear reaction. It was the first privately built non-light-water reactor to do that in the U.S. in more than 40 years, and four rival startups matched the feat within nine weeks.
Updated Aug 8
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