JAS (Japanese Amateur Satellite), also called Fuji, was a series of Japanese Amateur Radio satellites.

The JAS satellites were developed and built by the Japan Amateur Radio League. The 26-sided polyhedral satellites weighted 50 kg and were powered by body mounted solar cells, which supplied 10 W. The satellite were 0.44 m in diameter, and 0.47 m long. A turnstile antenna ring at its base received signals and four transmitting antennas extended from the top.

Fuji 1a mission was to provide analog and digital international satellite communications for radio amateurs, to study satellite tracking and control techniques, and to confirm the on orbit functions of the on board transponder developed by the amateur radio transpose group. It was renamed Fuji-OSCAR 12 in orbit.

MABES (Magnetic Bearing Flywheel Experimental Satellite), also called Jindai, was launched by a two-stage H-1 launch vehicle from the Tanegashima Space Center of the National Space Development Agency of Japan.

The MABES mission was to measure levitating / oscillatory / rotating characteristics of the magnetic bearing flywheel under zero G conditions and to confirm the function of the launch lock mechanism. The MABES experiment remained attached to the second stage of the H-1 launch vehicle.

The EGS (Experimental Geodetic Satellite), also called Ajisai, mission has 2 primary objectives. The first objective, which was short term, was testing of JAXA's H-1, 2-stage, launch vehicle. The second and primary long term objective was to determine the exact positions of the many isolated Japanese Islands. Ajisai can also be used for directional and photometric observations, using the mirrors equipped on the surface of satellite.

Satellite laser ranging to Ajisai is used to precision orbit determination and is used to improve the gravity field.

Ajisai has the following instrumentation onboard:

-318 Mirrors
-retro-reflector array (RRA) consistings of 1436 cube corners