Extraterrestrial solar energy and its possible variations

Values of the solar constant and solar spectrum have been adopted as design standards for NASA space vehicles and as engineering standards by IES/ASTM. High resolution spectral data for the UV and visible range, normalized to these standards have been derived. Applications of these results for weather analysis, air pollution, ozone production, and atmospheric energy exchange are reviewed. Indications of possible variations in solar energy, total and spectral, and their influence on the earth-atmosphere system are examined. Programs for future studies of these variations from satellites and high-altitude aircraft are discussed.