Direct measurement of solar luminosity variation
Science (New York, N.Y.)
|January 11, 1980
Summary
Measurements from two rocket flights suggest a 0.4% increase in solar luminosity (solar constant). This observed change in the Sun's brightness is likely real and warrants further investigation into its cause and potential climate impact.
Area of Science:
- * Solar physics and atmospheric science.
- * Radiometry and instrument calibration.
Background:
- * Accurate measurement of solar luminosity is crucial for understanding Earth's climate and solar variability.
- * Previous studies have explored short-term solar fluctuations, but long-term trends require precise, consistent measurements.
Purpose of the Study:
- * To assess changes in solar luminosity using an absolute pyrheliometer over a 30-month period.
- * To evaluate the reliability of the measurements by considering instrument performance and calibration.
Main Methods:
- * Two rocket flights were conducted using an absolute pyrheliometer to measure solar irradiance.
- * Instrument performance was evaluated, and pre- and post-flight intercomparisons were made with other pyrheliometers.
Main Results:
- * A 0.4% increase in solar luminosity (solar constant) was detected between the two flights.
- * Instrument intercomparisons suggest a high probability that this measured difference is a real solar variation.
Conclusions:
- * The observed increase in solar luminosity is likely a genuine phenomenon.
- * Further observations are needed to determine if this change is a random fluctuation, a short-term event, or a sustained shift with climatological significance.
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