The DEBUT (Deployable Boom & Umbrella Test), also called Orizuru, tested the deployment and retraction of a boom and an umbrella as an aerodynamic brake. Powered by batteries, it had only a short life time.

It succeeded JAS 1 (Oscar 12), Japan's first communications satellite linking amateur radio operators. JAS-1B operated as a store and forward message service. Uplink frequency was 144 MHz; downlink was 435 MHz.

MOS-series satellites orbit the Earth at an altitude of 909 km in 103 minutes always facing their observation equipment to the Earth. Each of them carries three sensors, Multispectral Electronic Self-Scanning Radiometer (MESSR), Visible and Thermal Infrared Radiometer (VTIR), and Microwave Scanning Radiometer (MSR), their observation data are acquired by overseas ground stations as well as our domestic data acquisition stations and utilized extensively.