Antares Nuclear, Inc.

Antares Nuclear, Inc., a small disadvantaged business headquartered in Torrance, California, develops advanced nuclear reactor and power systems for military and space defense applications, operating exclusively as a prime contractor (100% of recent awards) under total small business set-asides and other transaction agreements.

Antares Nuclear's capability portfolio centers on microreactor systems, nuclear electric propulsion, power conversion equipment, thermal management hardware, and high-temperature radiator coatings for defense space platforms and expeditionary installations. The company's recent work includes a $435.6 million Other Transaction Agreement with the Office of the Secretary of Defense for the JANUS Program on Advanced Nuclear Reactors for Military Bases and Installations (award date July 10, 2026, completion November 30, 2030); a $12.3 million OTA with Air Force Research Laboratory for the Advanced Nuclear Power for Installations (ANPI) program (award date August 13, 2025, completion March 31, 2027); a $4.2 million firm-fixed-price definitive contract with AFRL for Nuclear Electric Propulsion to Achieve Dynamic Space Operations (NEPADSO) (award date January 30, 2026, completion May 1, 2028); and a $1.22 million NASA SBIR Phase II award for unspecified nuclear technology development (award date September 30, 2026, completion September 29, 2028). Across multiple SBIR Phase I and Phase II actions from AFRL, the company has delivered rapidly deployable microreactor design, high-temperature radiator coatings, space-based neutral particle beam systems, and nuclear power conversion systems.

Customer concentration is extreme and mission-critical: the Office of the Secretary of Defense anchors 94.6% of combined potential value ($435.6 million of $460.7 million) through the single JANUS OTA, while the Department of the Air Force Materiel Command Research Laboratory (AFRL) accounts for 7 awards totaling $22.2 million across SBIR and development contracts. NASA and the broader Air Force together represent $2.8 million in potential value. All eleven awards are prime contracts or OTAs; Antares Nuclear operates a 100% prime footprint with no subcontract activity across the recent portfolio.

Activity shows growth year over year — one award in 2023, three in 2024, three in 2025, and four in 2026 — but the growth trajectory is driven almost entirely by the JANUS OTA's $435.6 million ceiling. Obligated dollars through recent awards amount to $46 million (10% of combined potential), reflecting the early-stage character of most contracts and the incomplete drawdown against the JANUS program. Five awards with ultimate completion dates within the next twenty-four months carry combined potential value of $20.9 million, exposing Antares Nuclear to recompete risk on multiple AFRL SBIR efforts and the ANPI OTA as those efforts conclude.