File:Sunspot butterfly with graph.gif

Butterfly diagram showing paired pattern of sunspots. Graph shows sunspot numbers.

• Spörer's law noted that at the start of an 11-year sunspot cycle, the spots appeared first at higher latitudes and later in progressively lower latitudes.

• The Babcock Model explains the behavior described by Spörer's law, as well as other effects, as being due to magnetic fields which are twisted by the Sun's rotation.

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Source weblink moved to: http://solarscience.msfc.nasa.gov/images/bfly.gif (dated checked: 2012/10/19)