Published: June 6, 2026 • 12:53 AM IST · Updated: June 6, 2026 • 3:40 AM ISTBy TheBriefWire Editorial Team
Key points
Just over a year ago, the Trump Administration issued an executive order meant to accelerate the development of nuclear power in the US.
While an entire startup ecosystem has developed around the use of different—and typically smaller—reactor designs, only one of them has been fully licensed so far, and there are no plans to actually build any instances of that design.
The executive order directed the Department of Energy to have three different reactor designs reach criticality in a bit over a year.
On Thursday, a startup called Antares announced that a test reactor it had placed at the Idaho Laboratory had reached criticality, making it the first new design to cross this threshold.
Criticality means that the nuclear reactions inside the hardware had become self sustaining;