Solar differential rotation determined by tracing coronal bright points in SOHO-EIT images

Abstract

Full-disc solar images obtained with the Extreme Ultraviolet Imaging Telescope (EIT) on board the Solar and Heliospheric Observatory (SOHO) were used to analyse solar differential rotation by tracing coronal bright points. The results obtained with the interactive and the automatic method for the time period June 4, 1998 to May 22, 1999 are presented and compared. A possible north–south rotational asymmetry and differences in the rotation velocity curves for various subtypes of tracers are investigated.