Japanese space-sustainability company Astroscale has unveiled plans for a mission it says will be the world’s first to inspect multiple defunct satellites in different orbits.
The mission, named In‑situ Space Situational Awareness-Japan 1, or ISSA-J1, is scheduled for launch in 2027 and will inspect two retired Japanese satellites in orbit. It follows the success of the company’s Active Debris Removal by Astroscale-Japan (ADRAS-J) mission, which delivered stunning close-up footage of a spent rocket stage in orbit.
“On-orbit inspection provides critical insight into the condition of satellites that cannot be obtained from the ground,” said Nobu Okada, managing director of Astroscale Japan, in a statement. “By inspecting multiple objects in different orbits in a single mission, ISSA-J1 will help demonstrate new capabilities that support satellite operators in understanding spacecraft condition and preparing for future servicing.”
The targeted satellites are the Advanced Land Observing Satellite (ALOS), launched in 2006, and the Advanced Earth Observing Satellite‑II (ADEOS‑II), launched in 2002. Once launched, the ISSA-J1 spacecraft will gradually approach ALOS, beginning observations at a distance before moving in for a closer inspection. ISSA-J1 will then transition into another orbit to repeat the process with ADEOS-II.
ALOS is about the size of a bus with a mass of around 8,800 lbs (4,000 kg). The satellite lost power in 2011 but remains in a near-polar orbit with an average altitude of 429 miles (691 kilometers). ADEOS‑II is slightly less massive at 8,150 lbs (3,700 kg) but in a higher near-polar orbit of around 500 miles (806 km) above Earth. The mission ended after less than a year due to the failure of a solar panel.
“Through this sequence, ISSA‑J1 will demonstrate the ability to approach multiple clients in different orbits within a single mission, repeating a cycle of approach, inspection, departure and orbital transition,” Astroscale said in a statement.
Astroscale was selected for the on-orbit inspection demonstration mission by the Japan Ministry of Education, Culture, Sports, Science and Technology as part of its Small and Business Innovation Research program. It is part of an effort to advance Japan’s space situational awareness and in-orbit servicing capabilities.
The company is also scheduled to launch the ELSA-M orbital debris removal demonstration mission no earlier than 2027 in partnership with Germany’s Isar Aerospace. The launch startup is currently preparing for its second-ever launch of its Spectrum launcher at Andøya Spaceport in northern Norway.