Impulse Space

Impulse Space is a Redondo Beach, California-based in-space transportation company founded in 2021 by Tom Mueller, SpaceX's first employee and the principal engineer behind the Merlin and Draco rocket engines that power the Falcon 9 rocket and Dragon spacecraft.

The company builds orbital transfer vehicles that move satellites and other payloads from where a rocket drops them off to the orbit they actually need to reach. Its product line includes Mira, a flight-proven maneuvering spacecraft used for last-mile delivery and repositioning within low Earth orbit, and Helios, a high-energy kick stage powered by the new Deneb engine that is designed to move payloads from LEO directly to geostationary transfer or geostationary orbit in under a day, cutting a trip that traditionally takes six to ten months down to a single day.

Impulse has raised more than $1 billion across five disclosed venture rounds since 2022, including a $45 million Series A led by RTX Ventures in 2023, a $150 million Series B led by Founders Fund in 2024, a $300 million Series C led by Linse Capital in June 2025, and a $500 million Series D in June 2026 that valued the company at $4.26 billion, with backers including Founders Fund, RTX Ventures, Lux Capital, Linse Capital, 137 Ventures, and Banner VC.

As of September 2026, Impulse Space remains privately held. The company has flown three orbital missions (LEO Express-1, LEO Express-2, and LEO Express-3), holds more than 30 signed customer contracts, was added to the U.S. Space Force's National Security Launch Program provider list, and has not filed for an IPO.