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Lectures on Stellar Statistics

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Published: 1921
Language: English
Wordcount: 18,362 / 71 pg
Flesch-Kincaid Reading Ease: 60.7
LoC Category: Q
Downloads: 648
Added to site: 2007.07.28
mnybks.net#: 17743
Origin: gutenberg.org
Genres: Science,
Excerpt

50[3]), but considering that the Pole-star ([alpha] Ursæ Minoris) is used at Harvard as a fundamental star of comparison for the brighter stars, and that, according to the observations at Harvard and those of HERTZSPRUNG (A. N. 4518 [1911]), the light of the Pole-star is very nearly invariable, we may say that the zero-point of the photometric scale is chosen in such a manner that for the Pole-star m = 2.12. If the magnitudes are given in another scale than the Harvard-scale (H. S.), it is necessary to apply the zero-point correction. This amounts, for the Potsdam catalogue, to -0m.16.

It is further necessary to determine the scale-ratio. Our magnitudes for the stars emanate from PTOLEMY. It was found that the scale-ratio--giving the ratio of the light-intensities of two consecutive classes of magnitudes--according to the older values of the magnitudes, was approximately equal to 2½. When exact photometry began (with instruments for measuring the magnitudes) in t

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David Niall Wilson
David Niall Wilson has had experiences in real life that can rival anything you would find in a novel. It is a good thing too, as the stories he collected while walking these strange and interesting paths has shaped him as a writer. David is not only the author of numerous novels and short stories, but also runs his own print, digital and audio publishing company. This makes him a busy man indeed, but we did manage to catch up with him to find out more about his novel, Nevermore, his fascination with history and some of his most unique travel experiences.
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