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Solar Variability (?) and Ice Ages. Most sunlike stars are variable. Our sun does have some poorly understood variability: Maunder minimum, 22-year magnetic cycle,… Standard Solar Model? Stable, non-convective core -- no variability. A. Meinel, M. Meinel, priv. comm.
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Solar Variability (?) and Ice Ages Most sunlike stars are variable. Our sun does have some poorly understood variability: Maunder minimum, 22-year magnetic cycle,… Standard Solar Model? Stable, non-convective core -- no variability. A. Meinel, M. Meinel, priv. comm. Variations in earth’s orbit (eccentricity, precession of poles, inclination) happen on these time scales, but don’t look much like this. The Question: Is the Sun’s radiant energy constant with time?
Test the Luminosity Constraint Neutrinos reach earth 8 minutes after they are produced. Photons take ~40,000 years. The neutrino flux is a measure of the solar luminosity, but thousands of years in the future. 1% is about 0.7 degrees. MeV-1cm-2s-1 The Luminosity Constraint: I = 85.31(34) x 1010 MeV cm-2 s-1 (solar irradiance)