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2026-06-08 Science & Technology

Antares reaches reactor criticality under Trump pilot program, marking major nuclear milestone

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Posted by Skidmark 2026-06-08 00:13|| E-Mail|| Front Page|| [1779 views ] Top

1 this is for a reactor w a capacity to deliver 250kW to 500KW

probably will need at least 4 of these to run a major air base or Naval Station

Not sure how much it weighs

Made in LA Calif.

Posted by Lord Garth 2026-06-08 10:03|| 2026-06-08 10:03|| Front Page Top

2 IIUC, these are intended for off-grid FOBs and the like to minimize fuel convoys.

Posted by Difar Dave 2026-06-08 10:50|| 2026-06-08 10:50|| Front Page Top

3 The great thing about making for the military is it soon finds its way into the commercial market. We have very safe reactors now and having them instead of the fraud "green" energy would do a lot more for making things cleaner.

Posted by DarthVader 2026-06-08 11:00|| 2026-06-08 11:00|| Front Page Top

4 Not sure how much it weighs

[AI]
how much does a microreactor weigh

Nuclear microreactors are designed to be highly portable, with specific weight constraints depending on the design and intended transport method. **Most microreactors weigh less than 40 tons**, allowing them to fit inside standard 40-foot cargo containers and be transported by truck, rail, or air.

* **Mitsubishi Heavy Industries** design: Approximately **40 tons** (3 meters tall, 4 meters wide).
* **U.S. Department of Defense** requirements: Less than **40 tonnes** for transportability via truck, ship, and C-17 aircraft.
* **Theoretical minimums**: Discussions on the smallest possible self-contained reactor suggest weights around **15 tons** for shielding and operation, though this is for very low-power experimental concepts rather than commercial power generation.

This compact size enables deployment in remote locations, military bases, and disaster zones without the need for extensive on-site construction.

Posted by Skidmark 2026-06-08 13:30|| 2026-06-08 13:30|| Front Page Top

5 [AI]
how much does a SpaceX rocket carry

SpaceX's current operational rockets have the following payload capacities to Low Earth Orbit (LEO):

* **Falcon 9**: Carries up to **22,800 kg** (50,265 lbs) to LEO, **8,300 kg** to Geostationary Transfer Orbit (GTO), and **4,020 kg** to Mars. It is a two-stage, medium-lift vehicle standing 70 m tall.
* **Falcon Heavy**: Carries up to **63,800 kg** (140,660 lbs) to LEO, **26,700 kg** to GTO, and **16,800 kg** to Mars. It is composed of three Falcon 9 cores and stands 70 m tall.

**SpaceX Starship**, which is currently in development and testing, aims for a significantly higher capacity. In fully reusable mode, it targets **100–150 tonnes** to LEO. It is a two-stage, super heavy-lift vehicle made of stainless steel, standing approximately 121–142 m tall depending on the block.

Posted by Skidmark 2026-06-08 13:33|| 2026-06-08 13:33|| Front Page Top

6 Need to get that height under 118 inches to fit on a 747 cargo aircraft

Posted by Dopey Photch2701 2026-06-08 14:47|| 2026-06-08 14:47|| Front Page Top

7 at 40 tons, trucks carrying the full microreactor would need an overweight permit (in addition to all the other permits)

does anyone know if the antares microreactor detachable into two components

Posted by Lord Garth 2026-06-08 15:04|| 2026-06-08 15:04|| Front Page Top

8 It would appear the fuel containment is separable.

Antares Mark-0 Becomes First Advanced Nuclear Reactor to Achieve Criticality Under DOE Pilot Program

Posted by Skidmark 2026-06-08 16:48|| 2026-06-08 16:48|| Front Page Top

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