A fungus (/ËfÊÅÉ¡És/; plural: fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from the other eukaryotic life kingdoms of plants and animals. A characteristic that places fungi in a different kingdom from plants, bacteria and some protists, is chitin in their cell walls.
The 11-year cycle of the number of sunspots was first demonstrated by Heinrich Schwabe (1789-1875) in 1843. There have been several periods during which sunspots were rare or absent, most notably the Maunder minimum (1645-1715), and less markedly the Dalton minimum (1795-1820) (Fig 2.8 in the book).
Sunspots are magnetic in nature. They are the places (active regions) where the Sun's magnetic field rises up from below the Sun's surface and those magnetic regions poke through. Sunspots are darker than the surrounding areas because they are expending less energy and have a lower temperature. Sunspots often have poles (polarity) like the south and north poles of magnets. Sunspots are formed continuously as the Sun's magnetic field actively moves through the Sun. The sunspots have lifetimes of days or perhaps one week or a few weeks. Here is one scenario that some scientists think explains how sunspots form.