The ADRAS-J2 mission, which plans to safely deorbit a rocket stage that has become a bus-sized piece of debris, is scheduled to take place before 2029. At least that’s what the Japanese company Astroscale promises.
Deorbiting space debris
Japan’s Astroscale recently signed a $90 million deal to deorbit a bus-sized rocket stage by the end of the decade.
The innovative project, funded by the Japan Aerospace Exploration Agency (JAXA), is a continuation of Astroscale’s ADRAS-J mission, which recently completed a close-range orbital inspection of the 12-year-old upper stage of Japan’s H-2A rocket.
The new mission, called ADRAS-J2, will capture a 3-ton rocket stage 36 foot long (11 m) with a robotic arm and pull it into Earth’s atmosphere to burn it up, demonstrating a critical technology for cleaning up space.
The H-2A upper stage, orbiting 370 miles (600 kilometers) high since deploying the GOSAT greenhouse gas observation satellite in 2009, is one of hundreds of spent rocket cases in near-Earth space. The uncontrollability and age of the rocket casing make it difficult to remove, but an ADRAS-J check showed that the payload adapter that would be used to capture the rocket was intact.
Other space debris removal missions
Astroscale is planning two more space debris removal missions. In July, the Tokyo-based company signed a contract with satellite operator Eutelsat OneWeb to deorbit a OneWeb satellite equipped with a magnetic docking plate in 2027.
Another concept spacecraft, Astroscale, equipped with a robotic arm, is under consideration by the UK space agency to potentially deorbit two old British satellites.
The ADRAS-J2 mission could be launched as early as 2027, according to the Space Assigned Numbers Authority. The European Space Agency (ESA) is also working on a mission that aims to remove space debris. This mission, called ClearSpace-1, will be directed at the much smaller 207 pound (94 kg) Proba-1 satellite. ClearSpace-1 was originally designed to remove a 247 pound (112 kg) payload adapter from Europe’s Vega rocket, but ESA decided to switch to Proba-1 after the initial target was damaged in an on-orbit collision in August 2023. The mission will be launched no earlier than 2028.
Astroscale also tested some of its key technologies in a project called ELSA-M. The mission, completed in January, repeatedly captured a simulated piece of space debris using a magnetic system.
Threats from space debris and the safe environment
Space debris is a serious problem. According to ESA, about 40,500 pieces of space debris larger than 10 centimeters are hurtling through space. These include old satellites, spent rocket stages, objects ejected from the International Space Station, and fragments from collisions and explosions. In addition, 1.1 million objects ranging in size from 1 to 10 cm are scattered in near-Earth space. The number of objects smaller than 1 cm is estimated at more than 130 million.
This debris is circling the Earth at incredible speeds, threatening to damage everything in its path. As the number of active satellites is also increasing, experts are concerned that collisions will soon become unpreventable because ground-based radars only see large fragments of space debris.
Collisions between large pieces of space debris are of particular concern because they create huge amounts of debris. Therefore, active space debris removal is crucial to keep the space environment safe for future operations, say many sustainability experts. An uncontrollable cascade of collisions called Kessler Syndrome can render it unusable for decades.
According to www.space.com
