Word: quasars
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...Quasars, most astronomers agree, are the oldest, brightest, farthest and most mysterious celestial objects known to man. To this list of superlatives, scientists at the Naval Research Laboratory have now added another. After recording X rays emanating from quasar 3C 273-the first time that a quasar has been identified as an X-ray source -Physicists Herbert Friedman and Edward Byram have determined that 3C 273 is also the most powerful X-ray emitter ever discovered...
...latest addition to quasar knowledge was obtained by instruments carried aboard an Aerobee rocket shot from White Sands, N. Mex., in May. Soaring above the atmosphere, which absorbs X rays before they reach the earth, the rocket detected X-radiation from quasar 3C 273, from a giant elliptical galaxy called M 87, and from three locations in the sky where no celestial objects are visible. The recorded radiation from the quasar was only one-thousandth as great as that from a starlike object called Sco XR-1-which appears to be the brightest X-ray emitter in the sky (TIME...
Astronomer Friedman would like next to monitor 3C 273's X-ray luminosity to determine if it varies as widely as the quasar's visible light. He would also like to get an X-ray spectrum, which might help unlock more of the quasars secrets. Either procedure would require a longer look at quasar X rays than can be obtained during the fleeting minutes that an X-ray telescope can be rocketed above the earth's atmosphere. The answer, Friedman says, is an X-ray telescope in an orbiting satellite or, better yet, one on the surface...
...spectrum, by a factor of 2.22. Just as the lowered pitch of the whistle of a receding train is determined by the speed at which it is traveling, 0237-23's red shift-the largest ever observed in a celestial body-indicates to most scientists that the quasar is receding from the earth at 153,000 miles per second. Because the speed of recession of stars and galaxies is thought to be caused by the expansion of the universe and is generally believed to be a measure of their distance from the earth, 0237-23 may be farther away...
Unlike the spectra of other quasars, which demonstrate one red shift in their emission lines and sometimes another in their absorption lines (caused by the passage of their light through cooler matter on the way to the observer), the spectrum of 0237-23 displays three red shifts. In addition to the expected shift of its emission lines, Astronomers Greenstein and Maarten Schmidt (TIME cover, March 11, 1966) have found its absorption lines have two distinctly different and lower red shifts. Astronomer Greenstein believes that they are caused by light from the central body passing through two shells of gas rapidly...