Ex-SpaceX Carlisle brothers build Argo Space around water as propellant

Robert, Ryan and Kirby Carlisle, three engineers who worked at SpaceX during the Falcon 9 era, founded Argo Space in late 2022 to build infrastructure in space. After launching, refurbishing and selling rockets at SpaceX, they chose to build spacecraft rather than rockets.

The company uses water as propellant. Water is potentially harvestable on the Moon and found across the Solar System, which the brothers see as a way to remove the need to use propellants from Earth. "We based the company on water," Robert Carlisle said in an interview.

Water also serves as coolant and radiation shield. Much of the spacecraft, from thrusters to avionics, is cooled by water, which raises the propellant mass fraction so the vehicle can go farther.

Argo Space flew its first demonstration mission, Navigator, in July on a Falcon 9 rideshare. The company made contact with the spacecraft, but one of its two rollout solar arrays failed to deploy. Controllers spent about half a day troubleshooting, and the spacecraft remained power-negative, draining its battery.

Sourcearstechnica.com