Word: cyclicality
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...pointed the newly invented telescope at the sun and saw black spots on its surface. So much for solar purity. Despite clerical disapproval, the reality of sunspots was quickly accepted. Still, more than two centuries passed before Samuel Heinrich Schwabe, a German apothecary and amateur astronomer, discovered the strange, cyclic behavior of the solar blemishes...
...hypothetical planet Vulcan, supposedly the closest one to the sun, hoping to spot it in silhouette as it moved across the solar disk. In the process, he observed and kept meticulous records of sunspots over a 17-year period. Finally, in 1843, he recognized and announced the eleven-year cyclic nature of the spots and wrote, "I may compare myself to Saul, who went to seek his father's ass and found a Kingdom...
Since the sun in myriad ways governs the very existence of all terrestrial life, the cyclic changes in the sunspot population have, ever since Schwabe, inspired speculation about their effect on solar radiation and, consequently, on the earth. Though the sun is a rather ordinary star, its vital statistics are breathtaking by earthly standards. Some 865,000 miles in diameter, it consists largely of hydrogen (72%) and helium (27%) and is 333,000 times as massive as the earth. Solar temperatures range from about 27 million degrees F* in the core, where 600 million tons of hydrogen are fused into...
...controversy has engulfed not only astronomers, geologists, paleontologists and astrophysicists but even evolutionary biologists. If the cyclic theory is true, the biologists argue, many assumptions about the course of evolution on earth--and even the likelihood of finding complex life forms on other planets--will be overturned. Says Whitmire: "Just the possibility that life here has been controlled by an astronomical event is very far reaching...
Among the various astronomers who considered and promptly rejected the galactic carrousel notion was California's Muller, a scientist obsessed by periodicity. If a familiar cosmic mechanism could not account for the cyclic nature of extinctions, he decided, something completely different would have to do. During Christmas break in 1983, Muller and fellow Astronomers Marc Davis of Berkeley and Piet Hut of the Institute for Advanced Study in Princeton were brainstorming about stars and periodicity, when Muller noted that more than half the stars in the galaxy are thought to be binaries (pairs of stars that orbit a common center...