Word: ultraviolet
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...best, Ehrlich figures, small bands of hunters and gatherers would be left in the Southern Hemisphere. And life would have difficulty renewing itself even after the dark and cold lifted, because most of the protective layer of ozone in the upper atmosphere would have been burned off. Killer ultraviolet radiation would stream in from the sun, paralyzing even phytoplankton, the one-celled ocean plants that form the base of the ocean's food chain. The effects would be less ghastly-but still catastrophic-if fewer megatons were exploded...
Doctors have long known that ultraviolet (UV) radiation from the sun produces profound changes in human skin. "Even one day's exposure can cause damage," says Dermatologist Fred Urbach of Temple University in Philadelphia. The most insidious rays are the short wavelength UVB, which prevail during the peak sun hours (between 11 a.m. and 3 p.m.). But new research has shown that even longer UVA waves, which are present all day, can promote skin cancer...
...Ultraviolet radiation has less obvious but even more pernicious effects. By altering proteins in the lens of the eye, it causes a gradual deposit of yellowish pigment. As with the tan, this pigmentation is beneficial up to a point; it helps shield the delicate retina from UV damage. But the dense accumulation of pigment after years of sunning is the main cause of cataracts...
...evils of ultraviolet are easily escaped. Mrs. Reagan had the right ideas when she resolved last New Year's Day to stay out of the sun. For those unwilling to make that sacrifice, the doctors at last week's conference urged the use of sunscreen lotions, some of which are now formulated to block both UVA and UVB. The Food and Drug Administration has published guidelines recommending a sunscreen of certain strength for each type of skin. For fair skinned people who never tan and always burn (Type I skin), sunscreens labeled with the number 15 are best...
Like most comets, I-A-A contains molecules of ammonia and nitrogen, along with water, presumed building blocks of the solar system. But another satellite, the International Ultraviolet Explorer, also found surprising indications of sulfur molecules. Said University of Maryland Astronomer Michael A'Hearn: "The sulfur may be one of the few things we see that actually reside in the comet's nucleus." The most stunning observational feat came when the big, 1,000-ft. radio telescope in Arecibo, PR., managed to bounce radar waves off the fleeting object and perhaps settled the old argument over whether cometary...