OSO 6

Description

OSO 6 was the sixth in a series of satellites designed to conduct solar physics experiments above the earth's atmosphere during a complete solar cycle. The primary objectives of OSO 6 were the acquisition of high spectral-resolution data within the 1 to 1300 A range, the observation of solar X-rays in the 20 to 200 keV range, and the observation of high-energy neutron flux in the 20 to 130 MeV range. Seven experiments were carried on the spacecraft. Two of these were located in the sail portion and were designed to point toward the sun. The remaining five experiments were mounted in compartments of the nine-sided rotating wheel section and scanned the solar disk every 2 s when the spacecraft was in sunlight. The spacecraft measured approximately 112 cm in diameter and about 96 cm in height. The spacecraft was spin-stabilized after launch, and gas jets mounted on the sail section kept the spacecraft positioned so that its spin axis was normal to the sun vector within plus or minus 3.5 deg. Servomotors drove the sail in a direction opposite to the spinning wheel so that the sail faced the sun during the sunlight portion of the orbit. OSO 6 was the first in the series that could offset point to any one of 16,384 points on a 128 by 128 point grid. With the spacecraft pointing at the sun center, large rasters of 46 by 46 arc-min could be performed. Small rasters, 7.5 by 7 arc-min, could be performed on any offset point but not outside the bounds of the 46 by 46 arc-min. The spacecraft was launched on August 9, 1969. All seven experiments were turned on for continuous operation by orbit 75 on August 14, 1969. The spacecraft was retired on December 31, 1972. For more information, see R. N. Watts, Sky and Teles., v. 38, p. 230, 1969.