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Show uu VARIABLE AND NEW STARS. "There are many stars in the sky w'hlch vary in brightness in a remarkable remark-able manner Every star is a great hot sun, millions of times larger than our little earth, and some of the stars which look to us to be single stars are really two suns so close together that they look to us like one. Sometimes Some-times one of these stars is very bright, and revolving around this bright star there is another which is less bright. And sometimes the darker dark-er star passes regularly between the bright one and us and so hides the bright star partly from us. In the northern sky there Is such a system called Algol, or the Demon Star Every Ev-ery two days and twenty hours the darker companion hides the bright sun partly from our view, and so cuts off five-sixths of the light of the bright star We see the star growing dimmer and dimmer for about three hours; at the end of this time the center of the darker star is directly in front of the center of the brighter one Then the darker one moves steadily past the star, and in tlme the star that had been dimmed shines out in full brightness. A little less than three days afterward we see the same thins happen again. But none of these stars shine so bright as first magnitude magni-tude stars, nor are thev made so faint by the darker star as to be wholly invisible to the eye. "Sometimes a 'new' star blazes out in the heavens. Perhaps, when this happens, a dark star has 'plowed' through one of the nebulous clouds in space, and its surface is thus heated heat-ed by friction from a dark crust to a brilliant vaporous mass. Or perhaps when we see such a new star it means that two stars have run into each other. oth-er. Exactly what happens when one of these new stars shines out, we do not yet know." Eric Doolittle in St. Nicholas. no |