From: Sam Wormley on
NASA Science News for July 27, 2010

Researchers using NASA's THEMIS spacecraft have discovered a form of
space weather that packs the punch of an earthquake and plays a key role
in sparking bright Northern Lights.

FULL STORY at

http://science.nasa.gov/science-news/science-at-nasa/2010/27jul_spacequakes/

A spacequake is a temblor in Earth's magnetic field. It is felt most
strongly in Earth orbit, but is not exclusive to space. The effects can
reach all the way down to the surface of Earth itself.