Word: ultraviolet
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Darkening Clouds. Could such a rare substance on earth be produced in quantity on Mars? Quite probably, say Plummer and Carson. The thin Martian atmosphere consists largely of carbon dioxide; it also contains a trace of carbon monoxide, which may be vented from Martian volcanoes. Under intense ultraviolet radiation from the sun, the two gases could combine into carbon-suboxide vapor. Indeed, the two scientists were able to simulate that very reaction in the laboratory. Their experiment also demonstrated that when the temperature is high enough, the vapor could solidify into a fine granular material, turn yellow and precipitate onto...
...rocket's nose cone contained two cameras designed to photograph ultraviolet light from the sun's thin outer layer or chromosphere in the few seconds that the moon blocked out the rest...
NASA's assumption was based on OAO-II's report of unexpectedly powerful ultraviolet radiation from half a dozen nearby galaxies. If this is true, NASA scientists reasoned, distant galaxies probably give off large amounts of the same invisible radiation. But those galaxies are receding from the earth (because of the expansion of the universe) at speeds that would cause ultraviolet light to shift toward the red end of the spectrum into visible frequencies. So the NASA men assumed the visible light from distant galaxies is intrinsically brighter than previously believed; therefore those galaxies must be farther away...
...first place, NASA's critics pointed out, ultraviolet radiation accounts for no more than a tenth of thz radiation from a galaxy. Thus, even a large increase in this component would not greatly affect a galaxy's overall brightness. Besides, modern astronomers always compensate for the "red shift" of light when viewing distant galaxies and quasars...
...cosmological calculations in no way detracts from the splendid performance of the Orbiting Astronomical Observatory. Operating in a 480-mile-high orbit above the polluted obscuring atmosphere and equipped with 11 telescopes, it has given astronomers a view of the skies unattainable on earth. In addition to its ultraviolet readings-which will almost surely contribute to knowledge about galactic structure-OAO II has discovered that young, "hot" stars are losing far more of their matter in the process of maturation than had hitherto been thought: as much as the mass of the earth in a single year. Data from...