Word: wavelengths
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...never got around to checking the paper of the album covers under ultraviolet light, or for watermarks. I have been told that the record itself fluoresces under UV light. Whether this is simply due to the diffracting characteristics of the record grooves being enhanced by using long wavelength light, I do not know...
...instrument builds up a picture by scanning the sun, back and forth and bottom to top, recording the intensity of ultraviolet radiation of a particular wavelength...
...kind of ions present at various levels of the sun's atmosphere depend on the temperature there. Each kind of ion, a chemical elements stripped of one or more electrons, emits a different wavelength of ultraviolet light...
...intensity of the ultraviolet radiation that accompanies a solar flare varies from one point of the spectrum to another. Also, at any one wavelength, the intensity varies as the flare moves through the sun's atmosphere. Ultraviolet light is a kind of thermometer, and these changes reflect temperatures varying from about 10,000 to about one million degrees centigrade. As it scans, the Harvard instrument will be recording the occurrence and spread of flares in every region. When the instrument is fixed on the center of the sun, it will provide more detailed information on how and where flares originate...
...hissing, noisy chorus. This discovery led to the science of radio astronomy, which has added to knowledge of the universe through radio telescopes tuned to various frequencies at the radio end of the electromagnetic spectrum. (The Harvard 60-foot radio telescope, for example, listens to 21-centimeter waves, the wavelength of emissions from neutral hydrogen gas. Hydrogen is the most abundant element in the universe...