In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
Q: These phenomena are counted using the Wolf number, and butterfly diagrams show the concentration of these regions in latitude bands. Coronal loops and mass ejections generally originate from these regions. Though they are not eclipses, they possess an umbra and penumbra. These electromagnetic phenomena go through a variation cycle of about (*) 11 years. For 10 points, name these cooler areas on the Sun's photosphere that appear dark.
A:
Science