Since the beginning of the space era with the launch of Sputnik I in 1957, humans have placed over 15,000 satellites into orbit. However, just over half of these satellites are still operational. The remaining satellites, having run out of fuel and reached the end of their useful life, have either disintegrated in the atmosphere or continue to circle the planet as nonfunctional pieces of metal.
This poses a threat to the International Space Station and other satellites. The European Space Agency has estimated that there have been over 640 incidents of "break-ups, explosions, collisions, or anomalous events resulting in fragmentation" to date.
This has resulted in a halo of space debris encircling the planet, consisting of 36,500 items larger than 10 centimeters (3.94 inches) and a staggering 130 million fragments measuring up to 1 centimeter (0.39 inches). The cleanup of this debris is both expensive and intricate, with numerous proposed plans but no concrete results as of yet.
One method to begin addressing this issue would be to cease the production of more debris by refueling satellites instead of decommissioning them once they exhaust their power supply.
Daniel Faber, CEO of Orbit Fab, states that at the moment, it is not possible to refuel a satellite while in orbit. His company, based in Colorado, is aiming to alter this reality. Faber emphasizes that when satellites deplete their fuel, they cannot maintain their designated orbit and pose a risk as space debris, moving at high speeds and potentially causing collisions. He also notes that the limited fuel availability leads to spacecraft missions being planned to minimize movement.
This implies that we are unable to have tow trucks in orbit to remove any debris that may be left behind. We are unable to conduct repairs, maintenance, or upgrades. We also cannot inspect anything if it malfunctions. There are numerous limitations to what we can do, and we operate within very tight constraints. This is the solution we are striving to implement.
NASA, in collaboration with DARPA and Boeing, first introduced the concept of refueling and servicing satellites in orbit with the groundbreaking launch of Orbital Express in 2007. This mission involved two purpose-built satellites successfully docking and exchanging fuel. Building on this achievement, NASA continued to explore the challenges of refueling existing satellites with the Robotic Refueling Mission (RRM). The agency is now focused on the upcoming OSAM-1 mission, scheduled to launch in 2026, which aims to grab and refuel Landsat-7, an Earth-observation satellite that has exhausted its fuel supply.
"This is a mission to refuel a satellite that was not designed for refueling," Faber explains. "They are essentially performing surgery on the satellite, cutting into it to access the fuel pipes. While this allows for impressive satellite repair capability, it comes with a significant cost." NASA estimates that OSAM-1 will total around $2 billion.
Orbit Fab is not planning to address the existing fleet of satellites. Instead, the focus is on equipping future launches with a standardized port known as RAFTI (Rapid Attachable Fluid Transfer Interface). This innovation would greatly simplify the refueling process, ultimately reducing the overall cost.
Faber explains, "Our goal is to develop an affordable architecture. Currently, there is no available commercial fuel port for satellite refueling in orbit. Despite all our grand visions of a thriving space economy, our focus is essentially on the fueling component - we are essentially a gas cap company."
A rendering of the futureÂ Orbit FabÂ Shuttle, which will deliver fuel to satellites in need directly on orbit.
Orbit Fab, known as the "gas stations in space," is developing a system that consists of fuel ports, refueling shuttles to transport fuel to satellites in need, and refueling tankers, or orbital gas stations, for shuttles to retrieve fuel from. The company has set a price of $20 million for on-orbit delivery of hydrazine, a commonly used satellite propellant.
In 2018, the company sent two testbeds to the International Space Station to test the interfaces, pumps, and plumbing. Then in 2021, it launched Tanker-001 Tenzing, a fuel depot demonstrator, which provided valuable insights for the design of the current hardware.
The upcoming launch is set for 2024, as Orbit Fab plans to deliver fuel in geostationary orbit for a mission by the Air Force Research Lab. "It's currently being treated as a demonstration, but there is significant interest from various branches of the US government who understand the value of refueling," says Faber.
Astroscale, a Japanese satellite servicing company, will be Orbit Fab's first private customer. They have developed LEXI, the first satellite designed for refueling, which will feature RAFTI ports and is slated for launch in 2026.
An original approach
According to Simone D'Amico, an associate professor of astronautics at Stanford University, who is not connected with Orbit Fab, on-orbit servicing is crucial for ensuring the safe and sustainable development of space. "Could you imagine a ground mobility infrastructure, roads and cities, without gas stations and auto repair shops? Could you imagine single-use cars or airplanes?" he asks. "The development of space infrastructure and the proliferation of space assets is reaching a critical volume that is not sustainable anymore without a change of paradigm."
The module that fueled the groundbreaking moon mission has now reentered Earth's orbit. D'Amico explains that there have been several factors delaying its return, such as the lack of demand for spacecraft maintenance and the recent economic feasibility of on-orbit servicing technology, thanks to advancements in satellite miniaturization.
He believes that Orbit Fab is truly innovative, particularly from a marketing standpoint. "It's likely the only company worldwide that has positioned itself to establish gas stations in orbit," he states. "I believe Orbit Fab's approach is truly visionary and has the potential to pay off in the medium to long term. However, there is high risk in the short term, as satellites need to be designed with reusability and refueling in mind."
Initially, Orbit Fab plans to establish itself in the market as a fuel supplier to companies such as Astroscale, who are planning satellite inspection, repair, and upgrades in orbit, as well as debris collection. According to Faber, success in this sector could then convince major telecommunications corporations, which operate a large number of satellites, to revamp their business model and adopt refueling and servicing.
His proposed timeline involves establishing a pattern of sending and delivering fuel in orbit, followed by manufacturing fuel in space within the next decade or so. He envisions building refineries in orbit to process materials launched from Earth into various chemicals, such as air and water for commercial space stations, as well as minerals for 3D printer feedstock and plant cultivation. Ultimately, his goal is for his company to become the leading industrial chemical supplier for the burgeoning commercial space industry.