Solar Radiation and Thermospheric Satellite

Taiyo
Mission typeSolar-terrestrial research
OperatorISAS
COSPAR ID1975-014A
SATCAT no.7671
Spacecraft properties
ManufacturerNippon Electric Company
Launch mass86 kg
Dimensions0.75 m × 0.65 m (diameter × height)
Power15 watts
Expedition
EndedJune 29, 1980
Start of mission
Launch dateFebruary 24, 1975, 05:25 UTC
RocketM-3C No. 2
Launch siteKagoshima Space Center
Orbital parameters
Reference systemGeocentric
RegimeLow Earth/Medium Earth
Periapsis altitude260 km
Apoapsis altitude3,140 km
Inclination31.54°
Period120 minutes

Solar Radiation and Thermospheric Satellite (SRATS), also knows as Taiyo ("Sun" in Japanese) or Shinsei-3,[1] was a space probe developed by the Institute of Space and Astronautical Science (ISAS) at the University of Tokyo. The probe was launched on February 24, 1975, from Kagoshima Space Center by M-3C-2 rocket. Its mission was focused on upper atmospheric physics, X-ray and UV solar radiation, and the Earth's ionosphere. Taiyo completed its mission before re-entering Earth's atmosphere on June 29, 1980.[2]

The satellite had a shape of octagonal cylinder (or prism), weighing 86 kg. It orbited the Earth in an elliptical orbit with a periapsis of 260 km and an apoapsis of 3,140 km, at a 32-degree inclination. The satellite's primary goal was to investigate solar X-rays, ultraviolet radiation, and the distribution of ions and electrons in the Earth's upper atmosphere.[2][3]

Instruments

Taiyo had seven science instruments:[2]

  • Solar X-Ray Detector (SXR): Designed to observe solar X-rays in two energy ranges (5.9-9.5 keV, 9.5-11.5 keV) and measure charged particles near the Earth's radiation belts.
  • Lyman-alpha Radiation Monitor (SXU): Measured solar hydrogen Lyman-alpha radiation to study the Sun's chromosphere.
  • Geocoronal and Middle Ultraviolet Radiometers (GMV): This system combined the Middle Ultraviolet Radiometer (MUV), which measured reflected solar light from atmospheric ozone, and the Vacuum Ultraviolet Photon Counter (GUV), which analyzed geocoronal emissions.
  • Bennett Ion Mass Spectrometer (CPI): Examined ion composition in the upper atmosphere, identifying H+, He+, and O+ ions.
  • Retarding Potential Analyzer (RPA): Measured ion density and temperature using voltage sweeps across ion traps.
  • Electron Temperature Probe (TEL): Recorded electron temperature variations, capable of measuring up to 4000 K.
  • Gyro-Plasma Probe (IMP): Analyzed electron density distribution through high-frequency impedance measurements.

Further reading

References

  1. ^ Darling, David. "Taiyo". www.daviddarling.info. Retrieved 22 October 2024.
  2. ^ a b c "DARTS for Astrophysics". DARTS at ISAS/JAXA. Retrieved 22 October 2024.
  3. ^ "TAIYO | Spacecraft". ISAS. Retrieved 22 October 2024.