Word: nebular
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Ever since man perceived that the solar system is a cohort of planets revolving around a central sun, at different distances but in the same direction and in almost the same plane, he has wondered how it all started. Pierre Laplace, French mathematician (1749-1827), devised the celebrated "nebular hypothesis": that the solar system was originally a diffuse, whirling, gaseous mass. As this nebular mass became smaller and denser, it whirled faster, until centrifugal force threw off a ring of gas. The process was repeated, each gas ring coalescing into a planet and the sun finally settling down...
Later astronomers abandoned the nebular hypothesis. They found two things wrong with it: 1) it was unlikely that the rings would gather into planets; 2) the "angular momentum" was wrong. Angular momentum can be roughly defined as the amount of rotation in a system. In the solar system the planets have about 98% of the angular momentum, but only one-seventh of 1% of the solar system's mass, the rest being in the sun. The Laplace theory could not account for this discrepancy. It seemed more likely that there had been interference from outside...
...spite of this lack of agreement on forms of the encounter theory, modern astronomers have favored the theory in general. But last week it looked as though the encounter theory was about ready for the scrap heap, along with the nebular hypothesis of Laplace...
Last week The Telescope, published by Harvard Observatory, pointed out that conclusions as to the size of the particles in this red nebula could be drawn from its color. If the nebular material were microscopically fine, the light of Antares would be reddened, just as the sun is reddened when it shines through a long slope of the hazy atmosphere at evening. Also, the light from the nebula would be made bluer by selective scattering of the same kind which makes the earth's sky blue.* Actually, the color of the star and that of the nebula are almost...
...parading through the heavens in the raiment of a beggar" was related by him last week at a meeting of the American Institute of Electrical Engineers in Manhattan. Forty years ago a British amateur named Denning spotted a faint blur in the constellation Camelopardus. It was identified as a nebular nucleus, or blob of cosmic matter. This apparently pusillanimous thing was of the twelfth magnitude, far below naked-eye visibility. Astronomers did not bother to name it but set it down by number, I. C. 342, in the Second Index Catalog (1895). With better cameras and telescopes...