(Submitted May 06, 1998)
How do sunspots affect the earth? Why?
The primary effect on the Earth is on our ionosphere.
This is the very upper part of the atmosphere.
Increased sunspot activity frequently accompanies an increase
in the outflow of matter from the Sun in the form of a "solar
wind". Charged particles in this wind can interact with atoms
in the upper atmosphere and sometimes wreak havoc with our
communications systems. It can interfere with the operation of
satellites by introducing background static. During periods of
heightened solar activity, the Earth's upper atmosphere swells up
slightly in response to the extra heating, which in turn
increases the rate of decay of satellites in low Earth orbit.
You can learn more about sunspots on our Solar System archive page, under "The Sun":
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