Impulse Space

Space Technology · In-Space Mobility · Aerospace

Funding

Impulse Space extends Series D by $308M, growing round to $808M

The valuation climbed from $4.26 billion to roughly $5.4 billion in just three months, signaling investor urgency around orbital logistics.

• Impulse Space closed a $308 million extension to its Series D round, growing the round's total to $808 million with participation from returning investors.
• Impulse Space builds spacecraft that move satellites and other payloads after launch, including the flight-proven Mira tug, the high-energy Helios kick stage, and the new electric-propulsion Electra system.
• The extension follows a $500 million tranche closed in June at a $4.26 billion valuation; the new capital values the company at roughly $5.4 billion, according to a source close to the company.
• Impulse's Helios spacecraft became the first upper-stage prime selected for the U.S. Space Force's NSSL Phase 3 Lane 1 program, alongside a $28 million contract extension for the VICTUS SALO 2 and 3 missions.
• The company has already sold out its Caravan 2 and 3 Helios rideshare missions for 2028 and plans to ramp Helios production alongside Mira, which has about half a dozen units in its factory today.
• Founder and CEO Tom Mueller was an early SpaceX engineer who helped develop the Merlin engine that powers the Falcon 9 rocket.
• As satellite operators increasingly rely on bulk rideshare launches, orbital tugs like Impulse's are becoming essential infrastructure for delivering payloads to precise final orbits, turning last-mile space logistics into a standalone market.