Interview Preparation

Impulse Space, the space logistics startup headed by founding SpaceX employee Tom Mueller, has closed a new tranche of funding to further develop its line of orbital transportation vehicles.

The oversubscribed Series A of $45 million was led by RTX Ventures, the venture capital arm of RTX (formerly Raytheon Technologies), and included participation from existing investors Founders Fund, Lux Capital, Airbus Ventures and Space Capital. Founders Fund led Impulse’s $20 million seed round in early 2022, while Lux Capital previously supported the company with a $10 million financing deal last summer.

Mueller is understood to be one of the leading propulsion experts alive todayAnd it’s a reputation he’s earned: As Employee Number 1 at SpaceX, he led the development of the Merlin and Draco engines, which power the Falcon 9 rocket and Dragon spacecraft, respectively.

The latter company, which Mueller founded in 2021, two years after his retirement from SpaceX, is also focused on propulsion. Impulse is developing a series of spacecraft that he calls “orbital maneuvering vehicles,” designed for last-mile payload delivery. That includes a vehicle called the Mira and a larger vehicle called the Helios. In a statement, Impulse said this latest round of funding will be used to further develop Helios, a high-energy boost stage that will be capable of bypassing geostationary transfer orbit and delivering payloads directly to geostationary orbit.

For the company’s first orbital mission, called Leo Express-1, Mira will perform a number of tasks in orbit, including last-mile payload delivery, payload accommodation, low-altitude maneuvering and atmospheric reentry. That mission is scheduled to launch on a SpaceX Falcon 9 rideshare mission in the fourth quarter of this year. The main client for that mission has not been announced.

The Redondo Beach, California-based startup has announced several other missions and partnerships, all of which are considerably more ambitious. The first is an in-orbit refueling demonstration mission with partner Orbit Fab scheduled for 2025. On that mission, Mira will serve as the hosting platform for Orbit Fab’s fuel depot and rendezvous with a US Space Force satellite to attempt to refuel.

Impulse was also chosen as the propulsion provider for Vast’s private station Haven-1, which is also scheduled to launch in 2025. If all goes to plan, that will be followed by a mission to mars (yes, Mars) with Relativity Space in 2026, for which Impulse is developing a Mars Cruise Vehicle and lander.