Solar Radiation and Thermospheric Satellite explained

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

• Hirao . Kunio . The TAIYO Mission . J.Geomag,Geoelectr. . 1975 . 27 . 4 . 265–270 . 10.5636/jgg.27.265 . 22 October 2024.
• Hirao . K. . Results of observations made by the SRATS (solar radiation and thermospheric structure) satellite. . Space Research Xvi . 1 January 1976 . 235 . 1976spre.conf..235H . 22 October 2024.
• Matsuoka . Masaru . Nagai . Fukuo . Ohki . Ken-ichiro . A solar X-ray detector aboard "TAIYO". . Journal of Geomagnetism and Geoelectricity . 1975 . 27 . 4 . 271–277 . 10.5636/jgg.27.271.
• Oshio . Takanori . Masuoka . Toshio . Higashino . Ichiro . Watanabe . Norihiko . An intensity monitor for solar hydrogen Lyman-.ALPHA. radiation (TAIYO SXU). . Journal of Geomagnetism and Geoelectricity . 1975 . 27 . 4 . 279–294 . 10.5636/jgg.27.279.
• Tohmatsu . Takao . Suzuki . Katsuhisa . Ogawa . Toshihiro . The atmospheric UV instrumentation for the satellite "TAIYO". . Journal of Geomagnetism and Geoelectricity . 1975 . 27 . 4 . 295–301 . 10.5636/jgg.27.295.
• Iwamoto . Iwao . Suitz . Takeshi . Fugono . Nobuyoshi . The Bennett ion mass spectrometer aboard "TAIYO" (CPI). . Journal of Geomagnetism and Geoelectricity . 1975 . 27 . 4 . 303–310 . 10.5636/jgg.27.303.
• Miyazaki . Shigeru . The retarding potential analyzer aboard the satellite TAIYO. . Journal of Geomagnetism and Geoelectricity . 1975 . 27 . 4 . 311–320 . 10.5636/jgg.27.311.
• Oyama . Koh-ichiro . Hirao . Kunio . Electron temperature probe experiments on the satellite "TAIYO". . Journal of Geomagnetism and Geoelectricity . 1975 . 27 . 4 . 321–330 . 10.5636/jgg.27.321.
• Oya . Hiroshi . Morioka . Akira . Instrumentation and observations of gyro-plasma probe installed on TAIYO for measurement of ionospheric plasma parameters and low energetic particle effects. . Journal of Geomagnetism and Geoelectricity . 1975 . 27 . 4 . 331–361 . 10.5636/jgg.27.331.

Notes and References

1. Web site: Darling . David . Taiyo . www.daviddarling.info . 22 October 2024.
2. Web site: DARTS for Astrophysics . DARTS at ISAS/JAXA . 22 October 2024.
3. Web site: TAIYO Spacecraft . ISAS . 22 October 2024 . en.