Register for an account


Enter your name and email address below.

Your email address is used to log in and will not be shared or sold. Read our privacy policy.


Website access code

Enter your access code into the form field below.

If you are a Zinio, Nook, Kindle, Apple, or Google Play subscriber, you can enter your website access code to gain subscriber access. Your website access code is located in the upper right corner of the Table of Contents page of your digital edition.

The Sciences

Ring of Fire

By Kathy A SvitilSeptember 1, 2000 5:00 AM


Sign up for our email newsletter for the latest science news

No, Earth is not being incinerated. The orange cloud enveloping the planet in this image is sunlight scattering off helium ions in the plasma sphereÑthe extremely rarefied, electrically charged bit of our atmosphere that extends 12,000 miles into space. This infernal view was beamed back by NASA's Imager for Magnetopause to Aurora Global Exploration (IMAGE) satellite, which monitors what happens when solar storms reach Earth.

Photo by NASA/IMAGE-EUV/Univ. of Arizona

A 27,000 mile-wide patch of sun shows a forest of plasma jets and loops. | Institute of Solar Physics for the Swedish Academy of Sciences

"We had almost no idea of what the plasmasphere looked like," says James Burch of the Southwest Research Institute in San Antonio, the principal investigator on IMAGE. "We thought it had smooth edges and long tails that extended out into space from the dusk side, but it is actually circular." The scalloped fringes of plasma on the upper left formed after a small magnetic disturbance from the sun passed Earth. "We don't really know why they are there," Burch says, but they appear to form before a full-on solar squall that could disruucommunications. Burch and the rest of the IMAGE team hope their satellite will allow scientists to track space storms, much as weather satellites now monitor thunderstorms.

    3 Free Articles Left

    Want it all? Get unlimited access when you subscribe.


    Already a subscriber? Register or Log In

    Want unlimited access?

    Subscribe today and save 50%


    Already a subscriber? Register or Log In