Sunspot (nonfiction)

Sunspots.

Sunspots are temporary phenomena on the photosphere of the Sun that appear visibly as dark spots compared to surrounding regions.

They correspond to concentrations of magnetic field flux that inhibit convection and result in reduced surface temperature compared to the surrounding photosphere. Sunspots usually appear in pairs, with pair members of opposite magnetic polarity.

The number of sunspots varies according to the approximately 11-year solar cycle.

Individual sunspots may endure anywhere from a few days to a few months, but eventually decay.

Sunspots expand and contract as they move across the surface of the Sun with a size ranging from 16 kilometers (10 mi) to 160,000 kilometers (100,000 mi) in diameter.

The larger variety are visible from Earth without the aid of a telescope.

In the News

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  Light beams reach Union Station untouched by war-era sunspots (1943).

Fiction cross-reference

• Sunspotter

Nonfiction cross-reference

• Light (nonfiction)

External links:

• Sunspot @ Wikipedia