The sun's shape and brightness
Kuhn, J. R.; Bush, R. I.; Scherrer, P.; Scheick, X.
United States
Abstract
We present satellite data that show that the sun's shape and temperature vary with latitude in an unexpectedly complex way. Although the solar oblateness shows no evidence of varying with the solar cycle, we find a significant hexadecapole shape term which may vary. We also see a variation of about 1.5 K in the surface temperature with latitude. Based on these results, we suggest that sensitive observations of brightness variations be used as a record of the surface 'shadow' of cyclical changes in the solar interior.