Axiom Space vs Vast

The International Space Station is approaching end of life, and these two companies are leading the race to build its commercial successors. Axiom Space leverages ISS heritage with modules that initially attach to the station, while Vast is building an independent station from scratch with ambitions for artificial gravity.

Station Architecture: ISS Attachment vs Independent

Axiom Space's strategy is to attach its first modules directly to the International Space Station, leveraging the ISS as a proving ground. The first Axiom module (AxH1) will dock to the ISS forward Node 2 port, followed by additional modules including a lab, a panoramic observatory, and a power/thermal module. Once the ISS is decommissioned (currently planned for ~2030), the Axiom segment will detach and operate as a free-flying commercial station. This incremental approach significantly de-risks the program — Axiom modules benefit from the ISS's existing life support, power, and crew support systems during the initial validation phase.

Vast is taking a bolder, potentially faster path: launching Haven-1 as a fully independent, single-module station on a SpaceX Falcon 9. Haven-1 is designed as an 18 cubic meter pressurized module that can host up to 4 crew, delivered via Crew Dragon. While smaller than Axiom's eventual multi-module station, Vast's approach avoids the complexities and timeline dependencies of ISS integration. Vast acquired Launcher (now Vast Access) in 2023 for its rocket engine technology and manufacturing capabilities, and has expressed long-term ambitions for a larger station incorporating artificial gravity through spin modules — a capability no commercial station has attempted.

Business Model & Revenue

Axiom Space is already generating revenue through its private astronaut missions to the ISS. The Ax-1 mission (April 2022) was the first fully private crew to visit the ISS, followed by Ax-2 (2023) and Ax-3 (2024, which included ESA-sponsored astronauts). Each mission costs approximately $55 million per seat. Axiom also holds the NASA contract to develop the Artemis III next-generation EVA spacesuit (AxEMU), providing an additional revenue stream and government relationship. These operational programs give Axiom something few space station startups have: actual flight heritage and current cash flow.

Vast is pre-revenue but well-funded, backed primarily by founder Jed McCaleb's personal fortune from co-founding Ripple and Stellar. The company has raised over $400 million and was selected as one of NASA's Commercial LEO Destinations (CLD) partners, providing a government anchor customer. Vast's revenue model centers on selling research time, microgravity manufacturing access, and crew accommodation aboard its station. The Launcher acquisition adds a potential propulsion and access services revenue stream, though Vast is years away from generating meaningful revenue from station operations.

The Post-ISS Landscape

NASA's plan to deorbit the ISS around 2030 creates both urgency and opportunity. The agency has committed to purchasing services from commercial stations rather than building an ISS successor, and has awarded CLD contracts to Vast, Blue Origin (Orbital Reef), and Nanoracks (Starlab). Axiom holds a unique position as the only company with an approved plan to physically attach to the ISS. The transition period is critical — NASA needs at least one commercial station operational before the ISS retires to avoid a gap in U.S. human spaceflight capabilities in LEO. Both Axiom and Vast are targeting launch timelines of 2025-2026 for their first hardware, making them the most likely candidates to have operational habitats before the ISS departs.