Solar variability due to sunspots and faculae

Journal Article · Tue Jan 20 04:00:00 EST 1987 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JD092iD01p00809· OSTI ID:6738192

Chapman, G A

Results of photometry of solar active regions and their effect on the solar irradiance in the visible part of the spectrum are presented. The effects of sunspots and faculae are given separately, since the measurement of sunspot irradiance fluctuations is less uncertain. It is argued that energy balance may exist between sunspot deficits and the facular excesses. The uncertainty however, is +- 15% (1sigma). This possible balance also depends on the correct mathematical model for the contrast of faculae as a function of position on the solar disk. Extreme Limb Photometer (ELP) data are presented in such a way as to show that the model for facular limb darkening is consistent with the assumptions inherent in the irradiance modeling. The ELP data support the notion that energy balance between spots and faculae is possible. It is emphasized that even if there is energy balance, there will still be variations in the solar irradiance at the earth. copyright American Geophysical Union 1987

• Research Organization: San Fernando Observatory and Department of Physics and Astronomy, California State University, Northridge
• OSTI ID: 6738192
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 92:D1; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTROMAGNETIC RADIATION
ENERGY BALANCE
PHOTOMETRY
RADIATIONS
SOLAR ACTIVITY
SOLAR CYCLE
SOLAR RADIATION
STARSPOTS
STELLAR ACTIVITY
STELLAR RADIATION
SUNSPOTS
VARIATIONS
VISIBLE RADIATION