Helion Polaris — 150M°C Plasma Milestone

Milestone

On 2026-02-13 Helion's 7th-gen prototype Polaris (suburban Seattle) reached 150 million °C — ~10× the sun's core — and became "the first privately developed fusion machine to operate with deuterium-tritium fuel."

Key Facts

• ~100M°C is the rough minimum threshold for sustained commercial fusion; Polaris cleared it.
• Future target fuel: deuterium + helium-3.
• Microsoft PPA: power from first 50 MW Orion plant (Malaga, WA), targeting first grid electrons in 2028 (widely seen as aggressive).
• As of late 2025 Polaris had not announced net energy production.

Entities

Sam Altman (chairman/backer since 2015), David Kirtley (cofounder/CEO), Reid Hoffman, Dustin Moskovitz (investors). Competitor: Commonwealth Fusion Systems (SPARC; Gates + Nvidia backed).

Caveats

Timeline questioned; unique approach unproven vs competitors; reactor assembly not yet begun.

Source: Sam Altman's fusion startup Helion hits 150M° milestone — Jordan Blum, Fortune, 2026-02-13. Full-text fetched.