Orbit Fab has tapped SpaceX to launch the first propellant depot in space as part of a rideshare that also includes the second of Intuitive Machines’ series of lunar landers. The depot, officially called Tanker-002, will be launched on a Falcon 9 rocket and maneuver close to a geostationary orbit around Earth.
Tanker-002 follows Orbit Fab’s successful launch of a propellant depot into low Earth orbit. This depot is designed to refuel satellites with its specially designed Rapidly Attachable Fluid Transfer Interface (RAFTI).
CEO Daniel Faber said in a press release issued by Orbit Fab, “Our robust RAFTI [the Rapidly Attachable Fluid Transfer Interface] system was designed to refuel large US Department of Defense, Intelligence Community, and commercial assets in geostationary orbit, so commencing operations in this orbit will be an important milestone for us. This GEO tanker will have the capability to store propellant for up to 15 years, though of course we provide the fuel that satellites need, where and when they need it.”
Previous proposals for a refueling station in space included some preliminary plans to make NASA’s Lunar Gateway capable of refueling spacecraft that are on their way to other parts of the solar system. This plan has fallen by the wayside partly due to lack of funding and partly due to an upswing of attention paid to the potential benefits of In-Situ Resource Utilization (ISRU). ISRU could reduce the costs of crewed missions to other planets like Mars by reducing the need to ship resources like rocket fuel to distant destinations and also potentially eliminate the need for a refueling station in lunar orbit.
Satellites in Earth orbit are typically limited to the fuel that they have on board when they launch. A series of propellant depots could expand the lifespan of satellites that are outfitted with the equipment needed to effectively top off their gas tanks.
According to Orbit Fab officials, Tanker-002 will actually reside a few hundred kilometers away from a true geostationary orbit when not in use in order to avoid cluttering up the geostationary zone. It may be capable of maneuvering to a satellite that needs refueling. A geostationary orbit requires an altitude of 35,768 kilometers, positioned above Earth’s equator, in order to perfectly match Earth’s rotation and stay above the same geographic location on Earth.
Communication satellites are typically placed in geostationary orbits, Starlink being one notable exception. SpaceX chose to place its thousands of Starlink satellites in low-Earth orbit to reduce latency, or the response time of a signal, as part of its efforts to make Starlink competitive against other satellite Internet services and even some “land line” broadband services. Other uses for satellites in a geostationary orbit include meteorology and navigation.
Tanker-002 is slated to launch in late 2022 or early 2023. Once launched, it will maneuver into position using one of Spaceflight Inc’s Sherpa-ES tugs.
Orbit Fab is financially backed by some of the heavy hitters in the aerospace industry, including Lockheed Martin and Northrop Grumman. This company has also made the finals in Tech Crunch’s Startup Battlefield. It refers to its planned series of propellant depots in orbit as the Gas Stations in SpaceTM depots.