• the (red-orange) image in a spectral line of singly ionized helium was taken at 304 Angstroms (top right), at 60,000 to 80,000 degrees Kelvin;
• in the (yellow) image at 284 Angstroms, ions of iron are viewed at about 2.0 - 2.5 million K. (14 times ionized iron)
• in the (green) image at 195 Angstroms, again ions of iron are viewed at about 1.5 million K. (11 times ionized iron);
• in the (blue) image at 171 Angstroms, ions of iron are viewed at about 0.9 - 1.0 million K. (8 and 9 times ionized iron)

Different features are viewed at different wavelengths. We want the differentiation in temperature so we can understand the flow of energy among features in the solar atmosphere, and what kinds of energy (thermal, mechanical, electromagnetic) are involved in creating, sustaining, and destroying the features. The brighter areas usually indicate a higher density of material, and thus, greater magnetic activity. All the images are digital, and record only the intensity of the light in the given bandpass. The colors are used for quick identification and to remind people that EUV radiation, like visible light, is composed of a variety of wavelengths -- colors -- that can tell us different things.

You can see some of the educational and outreach materials we have at the SOHO Classroom

Please visit our Newsroom for press releases and media coverage.

Previous Picks of the Week

SOHO began its Weekly Pick some time after sending a weekly image or video clip to the American Museum of Natural History (Rose Center) in New York City. There, the SOHO Weekly Pick is displayed with some annotations on a large plasma display.

If your institution would also like to receive the same Weekly Pick from us for display (usually in Photoshop or QuickTime format), please send your inquiry to steele.hill@gsfc.nasa.gov.