Almost a decade ago, a Spanish system was developed to collect the enormous amount of space debris (tens of thousands of disused satellites). Unfortunately, it was not very successful. NASA also contributed, in its own way, to avoid adding more cosmic junk, launching wooden satellites, but these initiatives were punctual and inefficient and space debris has been increasing for decades. At least until now, thanks to the Japanese company Astroscale that has not only put get to work, but has already launched the first collection satellite.
On February 18, aboard a Rocket Lab rocket, Astroscale launched ADRAS-J (acronym for Active Debris Removal by Astroscale-Japan). Two months later, the satellite was placed within a few hundred meters of its first target: the second stage of an H-IIA rocket launched in 2009 by the Japan Space Agency, JAXA. Finally, on May 23, ADRAS-J approached within 50 meters of the gigantic piece of space debris measuring more than 10 meters long, 4 meters in diameter and weighing 3 tons.
To do this, the ship used its twelve thrusters in a pioneering maneuver, according to the company statement. But it is not the only milestone, according to Astroscale. ADRAS-J successfully completed the safe and controlled approach to an unprepared space debris object at a relative distance of approximately 50 meters, collecting more images and data while maintaining a fixed-point relative position controlled from the upper stage.
“ADRAS-J is an innovative mission: the world’s first attempt to safely approach, characterize and study the status of an existing piece of large debris through encounter and proximity operations – the statement explains -. ADRAS-J is designed to rendezvous with an unprepared Japanese upper stage rocket body, demonstrate proximity operations, and collect images to evaluate the movement of the rocket body and the condition of its structure. “Unprepared orbiting objects pose an additional challenge as they are not designed with any technology that would allow docking or their potential maintenance or removal.”
The ADRAS-J mission has achieved several milestones since rendezvous operations began on February 22. During this phase, the ADRAS-J spacecraft began maneuvering into orbit using GPS and ground observation data. By April 9, ADRAS-J had successfully detected its target thanks to the onboard camera and the proximity approach phase began.
“When ADRAS-J was a few kilometers from the rocket wreckage – the statement added – the ground team successfully transferred navigation control to the onboard infrared camera with developed model matching navigation (MMN) algorithms. by Astroscale. This navigation method estimates relative distance by comparing captured images or data with a pre-existing model. On April 16, ADRAS-J began using MMN to process data on rocket characteristics such as shape and attitude, and on April 17 it successfully approached to a relative distance of several hundred meters. In May, ADRAS-J approached safely and successfully to its target, approximately 50 meters, and made observations of fixed points.”
In the next phase, ADRAS-J will attempt to capture additional images of the upper stage through several controlled approach operations. The images and data collected are expected to be crucial to better understand the debris and provide critical information for future removal efforts.