Commercial Space Launch Startups funded by Y Combinator (YC) 2026

Velontra is building a hypersonic space plane that can takeoff from anywhere in any weather. This horizontal takeoff increases launch reliability and enables customers to directly access any orbit. Our air-breathing propulsion system is up to 6 times more fuel efficient than any rocket, and uses oxygen from the air which creates thousands of pounds of additional payload capacity. We have millions in current government/commercial contracts and LOI’s. We have assembled a team of industry experts, government senior executives, and a NASA astronaut. The hypersonic space plane will work by taking off from any runway with a jet propulsion system. Next, it will climb to over 100,000’ and Mach 5. At this point, it will launch a 2nd stage rocket directly into the desired Low Earth Orbit. Velontra is “boldly going where no one has gone before.”

Epsilon3 is the AI-Powered ERP, MES, and Test Management Software for Complex Engineering, Manufacturing, & Operations. We are a growing team of engineers from SpaceX, NASA, Google, and Stanford with unique experience planning and executing over 100 space missions. We are applying what we learned to develop web-based solutions that make building and operating advanced systems as efficient, error-free, and enjoyable as possible. Want to join a fully remote, US-based SaaS startup on a mission to solve complex problems in aerospace, energy, defense, maritime, and biotech? Apply today!

Momentus is a space infrastructure services company. As a first mover, Momentus will offer the most basic, foundational services that enable businesses to flourish in space. With their experienced team of aerospace, propulsion, and robotics engineers, Momentus makes and operates cost-effective and energy-efficient in-space transport and service vehicles that utilize water plasma propulsion technology. Momentus has service agreements in place with numerous private satellite companies, government agencies, and research organizations.