Picture of the day - July 23, 2006

Viewing The Sun In "A Different Light"

Photo courtesy of NASA.   When we look at the sun we see a large, brightly glowing ball that is so bright it can damage our eyes if we look directly at it for more than a fleeting glance. But the sunlight that we can see with our human eyes consists of only a small fraction of the various wavelengths of energy emitted by the sun and other stars! The sun is a gigantic nuclear furnace that constantly emits energy in the form of electromagnetic waves. In order of the longest wavelength to the shortest, these electromagnetic waves include radio waves, microwaves, infrared light, visible light, ultraviolet light, X-Rays and gamma rays. Although we're very familiar with the everyday uses of most of these electromagnetic ranges, the only one we can actually see with our naked eyes is visible light - hence its name. The reason the sun looks so dark in today's picture is because you're only seeing the ultraviolet portion of the energy that is emitted (through the magic lenses of scientific instruments). Only the most active parts of the sun's surface emit significant amounts of ultraviolet light, so the sun appears mostly dark when everything but the ultraviolet range is filtered out. Picture Of The Day Homepage | Submit a photo Interesting Articles