The U.S. is building a fuel depot in space

Some 22,500 miles above Earth, a spacecraft filled with thruster fuel will gas up two orbiting Space Force assets.

The high-altitude endeavor, undertaken by the orbital servicing enterprise Astroscale U.S., is slated to occur in the summer of 2026, the company announced this week. This Department of Defense-funded mission will see Astroscale's 660-pound craft refuel a satellite with the propellant hydrazine, then maneuver to a fueling depot to fill up with more fuel, and then refuel another asset. (All the involved assets haven't yet been revealed by the Space Force.)

It will be the first time a Space Force craft is refueled in orbit. Such a fuel shuttle could keep missions in space longer and eliminate the need for any craft to suspend its mission to retrieve thruster propellant. It's a novel type of full-service gas station.

"This changes fundamentally how we do things in space," Ian Thomas, Astroscale U.S.' Refueler Program Manager, told Mashable.

After launching, the refueled craft will travel to a region called geostationary orbit, which is a unique place around Earth where spacecraft orbit at same rate Earth is rotating — meaning they stay locked in the same position relative to our planet. There, Astroscale's craft will carefully approach its first Space Force satellite target, called Tetra-5, and transfer fuel. The refueler will then thrust away and inspect the scene with a specialized camera to ensure no valuable fuel is leaking. Then, the refueler will fly to a nearby fuel depot, or gas station, and attach and pull fuel from the depot before traveling to its second refueling target.

"The point of the mission is to make sure all the different parts are viable and work," Thomas explained. "You have a fuel depot, a client, and us."

How Astroscale's refueler, "ASP-R," will approach and refuel spacecraft in orbit around Earth. Credit: Astroscale U.S.

For an outer space operation, while certainly not simple, it's relatively efficient once the refueler arrives at a spacecraft running on empty. "It is definitely longer than refueling your car but it's something that can be done in a matter of hours," Thomas said.

You've probably noticed that most spacecraft, whether satellites or NASA deep space probes, are fitted with solar panels. These are invaluable, as they provide power to a craft's computer systems, cameras, and beyond. But they can't provide propellant to move and reorient craft, avoid high-speed space junk, or keep a satellite from naturally getting dragged into Earth's atmosphere. That's why refueling is vital.

If a spacecraft can be refueled, engineers can design missions that aren't limited by fuel. The revolutionary, $10 billion James Webb Space Telescope, for example, has finite fuel, and its mission (while still lengthy) is limited to some 20 years.

"The paradigm we had doesn't hold up any more," Thomas emphasized.

An artist's conception of Astroscale's refueler orbiting Earth. Credit: Astroscale U.S.

This Tweet is currently unavailable. It might be loading or has been removed.

This isn't Astroscale's first orbital rodeo. In a separate mission intended to deorbit large pieces of space debris (called Active Debris Removal by Astroscale-Japan), the company has already closely approached a large rocket stage to test close proximity maneuverability and reconnaissance; next up, an Astroscale spacecraft will use a robotic arm to bring the large 36-foot-long spent rocket stage down to Earth, in 2028.

But before then, the company may prove that running a fuel depot in Earth's orbit isn't just feasible; it could redefine how expensive orbiting spacecraft — whether used for national security, communications, or science — operate in space.

"If you run out of fuel, you run out of life," Thomas said.