Impulse Space Raises $500M Series D After Recent Mira Propulsion Failure

Impulse Space announced a $500 million Series D funding round this week. The round was led by 137 Ventures and BANNER VC, with participation from Founders Fund, Lux Capital, and Linse Capital. The company plans to use the capital to hire as many as 200 new employees and to build and test more space vehicles.

President and COO Eric Romo told TechCrunch that the funds will support expanded production at a time when aerospace talent remains in high demand. Impulse Space was founded by Tom Mueller, a former SpaceX engine engineer.

U.S. Space Force buyers. It is also building Helios, a vehicle designed to carry satellites rapidly to high orbits after initial drop-off closer to Earth. Impulse Space started with a focus on propulsion and later expanded into full spacecraft construction.

This shift required the company to add engineers experienced in vehicle structures and flight computers. The company recently opened an office in Colorado to access a broader pool of aerospace talent. Romo, who joined SpaceX as its 13th employee in 2003, said his early work involved creating computer simulations of engine designs.

“I considered it success if I got within 20% of the right answer, because the simulations were just not that good,” he said. He added that while simulations have improved, physical testing remains essential. Romo noted that AI tools are being adopted by the company’s software teams.

He said deep learning models are not yet ready to solve complex hardware engineering problems because suitable training data is scarce. “If you want to go, say, find the best designs for a turbo pump seal package in the world, you’re not going to find those online,” he said. Mira completed its third flight late last year.

A navigation system issue caused the spacecraft to expend much of its propellant early in the mission. Romo said the company is preparing another Mira mission expected to launch before the end of the year.