Solar constant: constraints on possible variations derived from solar diameter measurements
Science (New York, N.Y.)
|June 22, 1979
Summary
Solar radius variations are linked to the sun's energy output. Historical data show minimal solar radius changes, suggesting stable solar constant over time.
Area of Science:
- Solar physics
- Stellar evolution
- Climate science
Background:
- The sun's energy output (solar constant) is crucial for Earth's climate.
- Variations in the solar constant may be linked to changes in the sun's physical properties, such as its radius.
Purpose of the Study:
- To investigate the relationship between solar constant variations and solar radius changes.
- To quantify historical variations in the solar radius.
Main Methods:
- Analysis of historical astronomical data concerning solar radius measurements.
- Solar modeling to infer solar constant variations based on radius changes.
Main Results:
- Available data constrain solar radius variations between 1850 and 1937 to approximately 0.25 arc seconds.
- Solar modeling suggests the solar constant did not fluctuate by more than 0.3% during the same period.
Conclusions:
- Historical solar radius variations are small.
- The solar constant has been relatively stable over the observed period, with implications for climate studies.
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