Reducing atmosphere that sodium is reduced and evaporated to produce the sodium tail of the Moon (see atmosphere of the Moon). Reducing atmosphere A reducing atmosphere is an atmospheric condition in which oxidation is prevented by removal of oxygen and other oxidizing gases or vapours, and which may contain actively reducing gases such as hydrogen, carbon monoxide, and gases such as hydrogen sulphide that would be oxidized by any present oxygen. In metal processing, a reducing atmosphere is used in annealing ovens for relaxation of metal stresses without corroding the metal. A non oxidizing gas, usually nitrogen, is used, or for more
Upper Atmosphere Research Satellite view of Earth’s limb. A vertical scan of the atmosphere was obtained by tracking the sun during occultation. The scan will measure the amount of solar energy absorbed by gases in the atmosphere. In order to support scanning, the instrument came in two parts, the optics unit on a two-axis gimbal and a fixed electronics unit. The optics unit contains a telescope that collects solar energy as well as the gas detectors. The electronics unit handles data, motor control and power for the instrument. HRDI observed the emission and absorption lines of molecular oxygen above the limb of the Earth,