Word: cygnus
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...theory is correct, there could be countless black holes among the billions of stars in every galaxy. But if no light or other radiation can escape from the bizarre objects, how can astronomers prove that they really exist? The answer may lie in the constellation Cygnus (The Swan), where scientists are now almost certain that they have located a black hole. Its presence was hinted at in 1971 by the first earth-orbiting X-ray satellite Uhuru, which detected a strong and widely fluctuating flow of X rays from Cygnus. Scientists suspected that the radiation source, which they named Cygnus...
Shortly thereafter, radio astronomers, using their more sharply focused antennas, picked up radio signals from the area. That gave a much more precise fix on Cygnus Xl, letting other astronomers train big optical telescopes on the site. There they found a huge star, a so-called class-B supergiant, at least 20 times as massive as the sun. It was traveling erratically through space, as if it were being tugged by a smaller companion star moving around it. From this gravitational pull, astronomers figured that the unseen star had at least three times the mass...
...their advanced skills, the sci entists of Cygnus made two important errors. In the first place, the signal they received contained no message at all. It came straight from Indonesia, where the volcano Krakatoa had erupted elev en years before, generating meaningless radio waves with its churning plasma...
Radio Galaxy. The strongest "radio star" in the sky had the astronomers baffled for many years. Its powerful waves came from a patch of sky in the constellation Cygnus, and optical astronomers could find nothing there. At last the Palomar telescope, guided by a new and extremely accurate radio fix, photographed an extraordinary scene that looked like a collision of two enormous galaxies 500 million light-years away. Galaxy collisions are possible, though unlikely, and they might emit radio waves because of churning gases between their hundreds of billions of stars...
...most radio astronomers no longer think that such a collision can properly explain the stupendous radio energy that streams out of Cygnus A. For one thing, the energy does not come from the central part that is optically visible. Strangely, it comes from two 'spots on opposite sides of the center. The sky is full of these double radio sources. One theory holds that they are galaxies that have exploded. Electrons released in the explosions may have been steered by magnetism and finally gathered at spots far away from the central wreckage. A vast catastrophe of this sort might...