Solar Asphericities from BBSO Synoptic Data and MDI Splittings
Abstract
Beneath the photosphere, on average the Sun is almost a perfect sphere. Historically, the main photospheric asymmetry studied has been the magnetic activity cycle as reflected in the Maunder butterfly diagram. In recent years, more subtle signatures of asymmetries varying with the solar cycle have been found. We have used temporal averages of BBSO synoptic maps from the activity minimum which has just ended to extract the low degree Legendre dependence of the data. We present preliminary comparisons of the degree of correlation between these Legendre coefficients varying through the solar cycle with the temporally corresponding low degree Legendre coefficents from MDI splitting data to enable us to garner another perspective, the role of the magnetic field in the Sun's cycle dependent asphericity.
- Publication:
-
American Astronomical Society Meeting Abstracts #194
- Pub Date:
- May 1999
- Bibcode:
- 1999AAS...194.4205G