Well...the sun rotates faster at the equator than the poles, so there is no true rotation period. We can speak of an AVERAGE rotation period of...31 days or so, but for any detailed studies we have to respect the fact that the sun rotates 'differentially' for purposes of tracking sunspots or other latitude-dependent surface phenomena.
All answers are provided by Dr. Sten Odenwald (Raytheon STX)
for the
NASA IMAGE/POETRY
Education and Public Outreach program.