Towards an Era of 'Getting Closer to See' in Orbit: Targets are Two Decommissioned Japanese Satellites Launched in the 2000s

Astroscale Holdings Inc. is working on on-orbit services, also known as 'space road services,' to realize a sustainable space environment. One of these services is inspection, where, much like a road safety patrol inspects a site, we approach a specific object in orbit, such as a malfunctioning satellite or debris, to understand its condition. Astroscale is now unveiling the target satellite debris and the overall mission profile for its demonstration mission of this service, scheduled for launch in 2027. **Mission Overview** As part of its on-orbit services, similar to various road services provided for automobiles, Astroscale is engaged in developing technologies for services like relocation, removal, and refueling. However, approaching the target object to assess its condition is indispensable for providing any service. Until now, space situational awareness has relied on ground-based observation or long-distance observation from orbit, limiting the information available about objects in orbits hundreds of kilometers high. At the same time, the need to know the deterioration and damage status of satellites and debris in orbit and their surrounding environment is growing across countries and sectors. We believe that in addition to ground-based observation, on-orbit patrols involving close approach and on-site inspection will become the new standard. This ISSA-J1 mission, as a demonstration of this 'space safety patrol,' will inspect two decommissioned Japanese satellite debris. Approaching and capturing close-up images of two satellite debris in different orbits is a world-first attempt for a private company*. Astroscale has also been selected as a grant recipient in the space field for the Ministry of Education, Culture, Sports, Science and Technology's Small and Medium Business Innovation Research (SBIR) Phase 3 fund project, which supports large-scale technology demonstrations by startups. The SBIR program aims to promote R&D by startups and smoothly implement their results into society, thereby fostering innovation in Japan. ISSA-J1 is a mission developed and operated as part of this initiative, addressing the 'Development and Demonstration of Technology and Systems for On-Orbit Satellite Debris Removal.' **Target Satellite Debris** In the ISSA-J1 mission, instead of approaching and inspecting a single piece of debris, we will approach and inspect two pieces of debris within the mission. By approaching multiple debris in a single mission, the demonstration will be more aligned with actual service provision. By observing multiple objects at a closer range than conventional observations, we will revolutionize on-orbit inspection. The targets for this mission are the following two decommissioned satellites launched by Japan in the 2000s. We will approach them in orbit, check their condition more than 20 years after launch, and investigate their attitude, rotation state, and secular changes. Advanced Land Observing Satellite (ALOS) Japanese name: 'Daichi' Operational period: January 24, 2006 (launch) - May 12, 2011 (end of operation) Size: Approx. 6m x 3.5m x 4.5m. Solar array paddle is 22m x 3m wide. Mass approx. 4 tons Altitude: Approx. 691km Advanced Earth Observation Satellite-II (ADEOS-II) Japanese name: 'Midori II' Operational period: December 14, 2002 (launch) - October 31, 2003 (end of operation)