Forecast: Heavy winds, plasma showers

From Washington, D.C., at the spring meeting of the American Geophysical Union

First view of Earth’s plasmasphere. The circle marks Earth and the line indicates its shadow. NASA

NASA has taken the first pictures from space showing the mysterious motions of ionized gas corralled by Earth’s magnetic field.

Launched March 25, the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) is depicting the region where this action takes place. New images show how the stream of charged particles emanating from the sun’s surface influences this layer, the magnetosphere.

From time to time, the solar wind intensifies, creating so-called magnetic storms as it slams into the  magnetosphere. These electromagnetic disturbances can disrupt power supplies and satellite and telephone communications.

“Two hundred years ago, you predicted a hurricane by watching the barometer fall,” says Patricia H. Reiff of Rice University in Houston.

“We’re at that point now. We’re getting the images so that we can understand the global dynamics of [a magnetic storm] and eventually be able to predict it much better.”

IMAGE uses three instruments to observe the shape and movement of clouds of ionized gas, or plasma. Another detector snaps images of protons striking Earth’s atmosphere. It captured the first picture from space of a proton aurora on May 5. Unlike the more familiar electron auroras, which generate visible light, proton auroras show up only at far ultraviolet wavelengths.

Another IMAGE device has taken the first global picture of the electrically charged layer, called the plasmasphere, that extends into space from Earth’s upper atmosphere.

“Fortuitously, now we are entering the maximum of the [11-year] solar cycle,” says mission leader James L. Burch of the Southwest Research Institute in San Antonio, Texas. “We expect there to be numerous, large magnetic storms during the 2-year IMAGE mission.”

More Stories from Science News on Earth