There’s a scene in the film Interstellar where Matthew McConaughey’s character flies his spaceplane up to meet a mothership spinning out of control. The protagonist rises to the challenge with a polished piece of piloting and successfully links up with his objective.
Real life, of course, isn’t quite this dramatic. Slow down that spin to a tranquil tumble, and replace McConaughey’s hand on the joystick with the autonomous wits of a computer, and you’ll arrive at an approximation of what a Japanese company Astroscale has accomplished within the last year.
Still, it’s an impressive feat of engineering and orbital dynamics. Astroscale’s ADRAS-J mission became the first spacecraft (at least in the unclassified world) to approach a piece of space junk in low-Earth orbit. This particular object, a derelict upper stage from a Japanese H-IIA rocket, has been in orbit since 2009. It’s one of about 2,000 spent rocket bodies circling the Earth and one of more than 45,000 objects in orbit tracked by US Space Command.
“This is the world’s first technology that allows any object orbiting the Earth at high speeds to be safely approached from the ground,” said Nobu Okada, founder and CEO of Tokyo-based Astroscale. “It has great potential.”
Mission success
Like most other space debris, the H-IIA rocket approached by Astroscale is uncontrolled, and lacks navigation aids or inter-satellite communication links that could help another satellite safely move in for a close look. This presents a more significant technical challenge than rendezvousing with a “cooperative” object like the International Space Station.
Ars reported on the progress of Astroscale’s ADRAS-J mission last August, soon after the spacecraft flew as close as 50 meters (164 feet) from the H-IIA rocket. ADRAS-J is the centerpiece of a public-private partnership between Astroscale and the Japan Aerospace Exploration Agency, which participated with a $13 million contract to co-fund the mission.
ADRAS-J, short for Active Debris Removal by Astroscale-Japan, launched in February 2024 to begin its pursuit of the H-IIA rocket in a polar orbit more than 350 miles (560 kilometers) above the planet. On November 30, ADRAS-J completed its final close approach to the H-IIA upper stage to reach a position just 15 meters (49 feet) from the rocket, using cameras and laser ranging sensors for autopilot navigation before backing away.
With this achievement, Astroscale unlocked its final milestone payment from the Japanese space agency, officials announced Wednesday. Part of Astroscale’s demonstration involved completing a 360-degree flyaround of the H-IIA rocket.
“This was acrobatic and super difficult technology,” Okada said last month in a briefing on Astroscale’s business outlook. “Please remember the debris is not sitting still. It is traveling around the Earth at seven to eight kilometers per second, which is (nearly) 100 times faster than a bullet train.”
Imagery captured by Astroscale showed the H-IIA upper stage to be in good condition, looking much like it did before it launched 16 years ago on a mission to deploy a Japanese climate research satellite. The remnant rocket is about the size of a city bus, while ADRAS-J is a little larger than a kitchen oven.
Is this really for space junk?
It will be up to a future Astroscale mission, named ADRAS-J2, to transit the last 15 meters to the H-IIA rocket. ADRAS-J was a pathfinder, and didn’t have the equipment to actually latch on to another object in orbit. Last year, Japan’s space agency awarded Astroscale a contract worth $88 million (13.2 billion yen) to build and launch ADRAS-J2 to rendezvous and use a robotic arm to attach itself to the same H-IIA rocket, then steer the discarded upper stage back into the atmosphere for a destructive reentry.
ADRAS-J2 is scheduled to launch in 2027, according to Astroscale.
Astroscale’s showcase in orbital ballet positions the company as a contender in the commercial satellite servicing industry, where business opportunities may eclipse the market for space debris removal, which Okada founded Astroscale to pursue in 2013. The company has subsidiaries in the United States, United Kingdom, France, and Israel to tailor offerings to customers in different parts of the world.
The US and European governments are now customers for Astroscale. The UK Space Agency and the European Space Agency partnered to award Astroscale approximately $35 million in government support for a demonstration mission named ELSA-M, slated to launch in late 2025 or early 2026 for an attempt to capture and de-orbit a defunct satellite in OneWeb’s broadband megaconstellation using a magnetic docking plate. This will differ from Astroscale’s work in Japan because the OneWeb satellite will be prepared to receive a visitor, unlike the H-IIA rocket.
Removing space junk from orbit sounds like a wonderful idea. It could reduce the chance of collisions generating more pieces of space debris. Spent rocket stages left in orbit are among the most concerning objects for space debris hawks because they might retain propellants or stored battery energy with explosive potential.
But the big question is who pays for such an undertaking? Removing just the 2,000 rocket bodies from orbit could probably cost tens of billions of dollars. Perhaps it’s worth launching a handful of cleanup missions to remove the most hazardous objects in orbit, such as large spacecraft or debris flying too high for atmospheric drag to force reentry for centuries or longer.
Therefore, it’s not surprising Astroscale has pivoted to other applications. The rendezvous and proximity operations (RPO) technology proven with ADRAS-J enables several other types of missions, such as satellite servicing and inspection.
Astroscale’s US subsidiary won a $25.5 million contract from the US Space Force in 2023 to build a satellite refueler that can hop around geostationary orbit. Like the ADRAS-J mission, this project is a public-private partnership, with Astroscale committing $12 million of its own money. In January, the Japanese government selected Astroscale for a contract worth up to $80 million to demonstrate chemical refueling in low-Earth orbit.
The latest win for Astroscale came Thursday, when the Japanese Ministry of Defense awarded the company a contract to develop a prototype satellite that could fly in geostationary orbit and collect information on other objects in the domain for Japan’s military and intelligence agencies.
“We are very bullish on the prospects for defense-related business,” said Nobu Matsuyama, Astroscale’s chief financial officer.
Astroscale’s other projects include a life extension mission for an unidentified customer in geostationary orbit, providing a similar service as Northrop Grumman’s Mission Extension Vehicle (MEV).
So, can Astroscale really do all of this? In an era of a militarized final frontier, it’s easy to see the usefulness of sidling up next to a “non-cooperative” satellite—whether it’s to refuel it, repair it, de-orbit it, inspect it, or (gasp!) disable it. Astroscale’s demonstration with ADRAS-J showed it can safely operate near another object in space without navigation aids, which is foundational to any of these applications.
So far, governments are driving demand for this kind of work.
Astroscale raised nearly $400 million in venture capital funding before going public on the Tokyo Stock Exchange last June. After quickly spiking to nearly $1 billion, the company’s market valuation has dropped to about $540 million as of Thursday. Astroscale has around 590 full-time employees across all its operating locations.
Matsuyama said Astroscale’s total backlog is valued at about 38.9 billion yen, or $260 million. The company is still in a ramp-up phase, reporting operating losses on its balance sheet and steep research and development spending that Matsuyama said should max out this year.
“We are the only company that has proved RPO technology for non-cooperative objects, like debris, in space,” Okada said last month.
“In simple terms, this means approach and capture of objects,” Okada continued. “This capability did not exist before us, but one’s mastering of this technology enables you to provide not only debris removal service, but also orbit correction, refueling, inspection, observation, and eventually repair and reuse services.”