Reported March 2006

BACKGROUND: Bursts of matter from the sun, called coronal mass ejections (CMEs), have long been known to affect cell phone reception, TV and radio signals, and how much radiation exposure we receive while flying in the upper atmosphere. Now, researchers have detected plumes that tell them where the radiation form the ejection is concentrated and what places will be influenced the most by the CME.

CME OR SOLAR FLARE? People sometimes confuse CMEs with solar flares, but they are different phenomena. Solar flares are explosions on the sun that occur when energy build up around sunspots, becoming so hot -- millions of degrees F -- they produce a burst of electromagnetic radiation across the entire electromagnetic spectrum, from radio waves to x-rays and gamma rays. CMEs were once thought to be the result of solar flares, but while they sometimes accompany solar flares, there is no direct relation between the two. They occur when a large bubble of plasma escapes through a star's corona and travels through space to the earth at high speeds over the course of several hours. If a CME collides with the earth, it can produce a geomagnetic storm, which can cause electrical power outages and damage communications satellites and electronic equipment. Solar flares, on the other hand, affect radio communications.

WHAT ARE PLASMAS: A plasma is essentially electrically charged (ionized) gas, consisting of free-moving electrons and ions (atoms that have lost electrons). Applying a surge of energy -- with a laser, for example -- knocks electrons off gas atoms, turning them into ions and creating a plasma. Unless this energy is sustained, however, plasmas will recombine back into a neutral gas. On earth, we are familiar with the ordinary states of matter: solids, liquids and gases. But in the universe at large, plasma is by far the most common form. Plasma in the stars and the space between them makes up 99 percent of the visible universe.

The American Geophysical Union contributed to the information contained in the TV portion of this report.

If you would like more information, please contact:

Anthea J. Coster, Ph.D.
MIT Haystack Observatory
Atmospheric Sciences
Westford, MA 01886
781-981-5753
ajc@haystack.mit.edu

For more information about solar flares and CMEs, contact:

American Geophysical Union
2000 Florida Avenue N.W.
Washington, DC 20009-1277 USA
Phone: +1-202-462-6900
(Toll Free in North America: 1-800-966-2481)
http://www.agu.org/

FACTOID...

The first recording of a geomagnetic storm (a disturbance in the earth's magnetic field) was made from May 1806 to June 1807 by Baron Alexander von Humboldt, from his home in Berlin, Germany.

ONTHE WEB...

Movie:
http://csep10.phys.utk.edu/