Getting to the Moon or Mars? Musk and Bezos tackle space travel's refueling problem

Elon Musk and Jeff Bezos are trying to figure out how to pump gas in space.

- Micah Maidenberg

The billionaire space rivals are working on ambitious missions to the moon or Mars, and a crucial design element for each venture is using spacecraft that take on additional fuel while orbiting Earth.

Vehicles that could grab propellants in orbit would be less weighted down at liftoff, letting planners design missions to travel farther from Earth with more cargo, scientific gear or crew members, advocates say.

Having in-orbit refueling that give spacecraft something like a truck stop to pull into may sound like science fiction. It is also a concept that engineers have been working on for years.

One of the biggest challenges to making it a reality: moving and storing massive amounts of supercold propellants that are prone to boil off in the void of space. Both SpaceX and Blue Origin have much to prove.

Some space-industry officials are skeptical that either will have moon landers that depend on orbital fueling ready to meet National Aeronautics and Space Administration timelines. The agency has worked closely with contractors to understand the challenges of in-space refueling, a NASA spokesman says.

SpaceX conducted a fuel-transfer demonstration inside a Starship spacecraft during a 2024 test flight and next year is aiming to move propellants between two vehicles.

That test has been delayed as the company has faced setbacks with the massive rocket, including an explosion during a ground test in Texas in June.

Blue Origin is developing a transporter vehicle that would take on propellant near Earth.

Then, it would fly to a lunar orbit, where the transporter would prepare a lander that would take astronauts arriving on a different ship down to the surface of the moon.

That mission depends on the company's New Glenn rocket, which the company launched for the first time in January.

Engineers have long built rockets and spacecraft to take on all the fuel they need while still on the ground.