Taiyo

Launch data: Designation 07671 / 75014A Launch date 24 Feb 1975 - 14:25 (JST) Launch site Kagoshima Space Center Launch vehicle M-3C (#2) Mission Scientific: ionosphere and Sun study Elliptical Earth orbit: Perigee / Apogee  260 x 3140 km Eccentricity   Inclination  32 deg Period  120 min

Spacecraft data: Prime contractor   Platform   Operator   Mass at launch  86 kg Dry Mass   kg Basic shape  Octagonal cylinder Dimension (m)  approx. 0.7m long from face to face, high: 0.71m Equipment   Solar array   Stabilization   Propulsion   DC power   Design lifetime

Scientific Instruments:

• Ultraviolet earth coronal bright line spectrum analyzer
• Electron density monitor

Decay:

Mission details:

• Objectives: Observation of solar soft X-ray, solar vacuum ultraviolet radiation, ultraviolet earth coronal bright lines, etc., to research upper-atmosphere physics.
• Operation: The radio-guidance system, which had been tested by M-3C-1, was used for the launch. During the first revolution after orbital insertion, spinning was slowed to 11.5rpm by activating the yo-yo despinner, then the probe was deployed. During the 4th and 5th days after launch, the satellite spin axis was set to be perpendicular to the orbital plane. On the 24th and 28th days, high-voltage power was input to the observation instruments and, after confirming their proper operation, observation started.
• Results: Over several years, TAIYO achieved its original mission of obtaining data on the earth's plasma environment while solar activity was calm. International research cooperation was performed with the West German AEROS-B satellite, which conducted similar observation.