Differential rotation

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Differential rotation" – news · newspapers · books · scholar · JSTOR (December 2009) (Learn how and when to remove this message)

Differential rotation is seen when different parts of a rotating object move with different angular velocities (or rates of rotation) at different latitudes and/or depths of the body and/or in time. This indicates that the object is not rigid. In fluid objects, such as accretion disks, this leads to shearing. Galaxies and protostars usually show differential rotation; examples in the Solar System include the Sun, Jupiter and Saturn.^[1]

Around the year 1610, Galileo Galilei observed sunspots and calculated the rotation of the Sun. In 1630, Christoph Scheiner reported that the Sun had different rotational periods at the poles and at the equator, in good agreement with modern values. ^{[citation needed]}