Impulse Space Raises $500M to Power the Next Space Race

Impulse Space has raised $500 million in Series D funding, giving the fast-growing rocket engine and spacecraft startup new momentum in the race to make space transportation faster, more flexible, and more affordable. The company was founded in 2021 by Tom Mueller, the propulsion expert known as SpaceX’s first hire and a key figure behind the company’s rocket engine development. Since its founding, Impulse has now raised more than $1 billion, showing strong investor confidence in the future of in-space mobility.

The new funding round was led by 137 Ventures and BANNER VC, with participation from Founders Fund, Lux Capital, and Linse Capital. Impulse plans to use the money to expand production, test more vehicles, and hire as many as 200 new employees. While many technology companies are cutting staff or leaning heavily on artificial intelligence, Impulse is taking a different approach. President and COO Eric Romo said the company still needs real engineers to design, analyze, build, and test complex hardware because AI tools are not yet ready to replace hands-on aerospace work.

Impulse’s main focus is in-space mobility, which means helping satellites and spacecraft move more effectively after they reach orbit. Its smaller spacecraft, Mira, has already flown three missions since its first launch in 2023. Mira uses a novel propulsion system powered by non-toxic propellants, nitrous oxide and ethane, and is designed for highly maneuverable operations in orbit. The company is also preparing another Mira mission expected to launch before the end of the year, after a previous flight faced a navigation issue that caused it to use much of its propellant early.

The company is also developing Helios, a larger vehicle designed to move satellites quickly from lower orbits to higher destinations, including geostationary orbit. Demand for Helios has been stronger than expected, especially from commercial customers looking for faster and more flexible ways to deploy satellites. Impulse expects Helios to debut next year on a rideshare mission called Caravan, which will carry smaller spacecraft directly to geostationary orbit. That first Caravan mission is already fully booked, with future opportunities planned for 2028.

Impulse’s growth is also tied to rising interest from the U.S. Space Force and NASA. The Space Force is increasingly focused on satellite mobility as the United States responds to potential threats from Russian and Chinese spacecraft. Being able to move quickly in orbit is becoming a major national security priority. At the same time, NASA’s Moon Base plans could create another major opportunity for Impulse. The company believes Helios could help deliver one to two tons of cargo to the lunar surface, far more than some current commercial landers can carry on similar launches.

Mueller has described Impulse’s mission as more than simply building spacecraft. He says the company is working on the economic and technical engine that could power humanity’s expansion into space. That vision explains why investors are paying close attention. As space becomes more commercial, crowded, and strategically important, simply reaching orbit is no longer enough. The next major challenge is moving efficiently once there, and Impulse Space is positioning itself as one of the companies that could define that future.

Works Cited

Berger, Eric. “Impulse Space Raises $500 Million as Orbital Maneuvering Race Heats Up.” Ars Technica, 2 June 2026, www.arstechnica.com/space/2026/06/impulse-space-raises-500-million-as-orbital-maneuvering-race-heats-up/. 

Fernholz, Tim. “Rocket Engine Startup Impulse Raises $500 Million to Hire People, Not AI.” TechCrunch, 2 June 2026, www.techcrunch.com/2026/06/02/rocket-engine-startup-impulse-raises-500-million-to-hire-people-not-ai/. 

Wall, Mike. “Unlocking ‘the True Space Age’: Impulse Space Raises $500 Million to Build Out Fleet of Ultra-Mobile Spacecraft.” Space.com, 2 June 2026, www.space.com/space-exploration/launches-spacecraft/impulse-spacex-500-million-investment-space-ultra-mobile-

spacecraft. 

“Impulse Mira Spacecraft in Orbit.” TechCrunch, 2026, techcrunch.com/wp-content/uploads/2026/06/Impulse-Mira-Spacecraft-In-Orbit-2.png. 

“Helios Kick Stage.” Ars Technica, 2026, cdn.arstechnica.net/wp-content/uploads/2026/06/Helios-kick-stage.jpg.