Solrad 9とは 意味・読み方・使い方

Solrad 9 was launched on March 5, 1968. The SOLar RADiation satellite program (SOLRAD) was conceived in the late 1950s to study the Sun's effects on Earth, particularly during periods of heightened solar activity. It served as a cover project for the Project Dyno ELINT intelligence satellites with the covernames GRAB and POPPY operated by the U.S. Naval Research Laboratory (NRL). Solrad 9 is a spin-stabilized satellite oriented with its spin axis perpendicular to the Sun-satellite line. Fourteen solar X-ray and ultraviolet (UV) photometers point radially outward from its equator to view the Sun with each revolution. Solrad 9 was heavily used until February 25, 1974, when its attitude control system gas supply was exhausted.