APRIL 25, 1998 TRACE IMAGE - This image is an active region on the limb (edge) of the Sun made using NASA's Transition Region and Coronal Explorer (TRACE) spacecraft. The high resolution of the TRACE ultraviolet light telescope reveals the fine structure in loops of plasma (hot, electrically charged gas) contained by strong magnetic fields. The false colors represent different temperatures; blue is approximately 360,000 degrees Fahrenheit, green is roughly 900,000 degrees Fahrenheit, and red is about 2.7 million degrees Fahrenheit. White is seen where all three colors combine, and thus plasma structures at all three temperatures are present. The thin loops with distinct temperatures and fine structure indicate that heating of the plasma tends to occur along small groups of magnetic field lines in very localized regions. Fifteen Earths placed side by side would fit inside the larger loops. TRACE was launched into orbit on Apr. 1, 1998 from Vandenberg AFB, Calif. This image is available on the internet at: http://www.gsfc.nasa.gov/ftp/newsmedia/TRACE/ . (Photo Credit: Dr. Alan Title/Stanford Lockheed Institute for Space Research and NASA)