Determination of the period of differential rotation of the Sun

Sun (6 November 2011). © Álvaro Folhas
Access the full demonstrator in the Inspiring Science Education website. You can also download the PDF.
Short description

Based on spectroheliograms provided by the Geophysical and Astronomical Observatory of the University of Coimbra, and using the Tracker (freeware), we ask three questions about the Sun:
– Is it the spherical sun?
– If it rotates, how long does it take to go around?
– Does it rotate like a rigid body?
Students will have to transform the sequence of images into data, which will assume a graphic representation and, after that, they must achieve the proper mathematical function that will be adjusted. Finally, students must exploring its physical meaning of this behavior and understand why it happens.