A CME, one type of "solar storm", erupts from the Sun in January 2002. The actual disc of the Sun, indicated by the white circle, is hidden in this view through an instrument called a coronagraph. The coronagraph creates an artificial eclipse by blocking the too-bright light from the Sun's surface, allowing us to view the Sun's dimmer atmosphere.
Click on image for full size
Images courtesy SOHO (NASA & ESA). Animation by Windows to the Universe staff (Randy Russell).

Related links:

Space Weather

Movie: A Computer Model of a CME - from the Sun to Earth

Movie: Journey Beneath a Sunspot

Movie: Geomagnetic Substorm Triggered by CME from Sun

A movie of a coronal mass ejection in white light, courtesy of the High Altitude Observatory (180K MPEG) Movie credit

Movie: Aurora and THEMIS Satellite

Ulysses/ACE Concentration Game

Coronal Mass Ejections

Have you ever seen an explosion before? Maybe you've seen a volcano explode on t.v. Or maybe you've seen a potato explode in the microwave because your mom forgot to poke holes in it. Well, explosions happen on the Sun too. We call these explosions coronal mass ejections or CME's. You can see a picture of a CME to the left!

Even though the Sun is very far away, these explosions on the Sun can affect things on Earth. Material that is thrown out from the Sun during a CME can disrupt radio communications or fry satellite electronics. This material can also cause strong geomagnetic storms, aurorae and power blackouts.

Because CME's affect Earth, we need to know when they are happening. Satellites like the ACE satellite act as a spaceweather station while in orbit. ACE can provide advance warning of any geomagnetic storms that would affect the Earth.

Last modified March 29, 2010 by Randy Russell.

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