MJOLNIR SPACEWORKS (MSW) is an aerospace startup headquartered in Sapporo that is industrializing hybrid rocket engines combining solid plastic fuel with liquid oxygen. Leveraging fuel-geometry research originated by Hokkaido University, the company has achieved commercial-scale thrust while maintaining the safety, throttling, shutdown, and restart advantages of hybrid systems. Its planned engine lineup includes the 370 mm-diameter "D370" and 540 mm-diameter "D540," delivering roughly 15–150 kN per unit or up to about 450 kN in clustered configurations, with burn times of 10–100 seconds. MSW also markets weld-less high-pressure propellant tanks that promise lower cost, faster lead times (as short as three months), and high cleanliness for spacecraft use. The firm’s strategy is to mass-produce these engines and tanks for rocket manufacturers worldwide, positioning itself as a low-cost, reliable propulsion supplier. Its latest capital raise brings total funding to ¥850 million, earmarked for product refinement, aggressive hiring, and accelerated overseas expansion.

Total raised

$3M

Funding rounds

1

Latest round

Series A

Latest activity

Oct 2025