A closeup view of a typical pair of sunspots, with Earth superimposed to show scale.
Click on image for full size
Original Windows to the Universe artwork by Randy Russell using images from the Royal Swedish Academy of Sciences (sunspot image) and NASA (Earth image).
Sizes of Sunspots
Sunspots are very large
structures. Although they look small against the backdrop of the Sun,
which has a diameter of 1.4 million km (870
thousand miles), most sunspots could swallow a planet. Many sunspots, like
the ones shown in the image on this page, are as large
as Earth! Most spots range in size from about 1,500 km (932 miles) to around
50,000 km (31,068 miles) in diameter. Occasionally gigantic sunspots the size
of Jupiter appear on the Sun's "surface".
Astronomers believe some other stars also have spots. Young stars seem especially
likely to have large numbers of starspots, and some of those
may be immense.
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