منابع مشابه
Magnitude systems in old star catalogues
Abstract. The current system of stellar magnitudes first introduced by Hipparchus was strictly defined by Norman Robert Pogson in 1856. He based his system on Ptolemy’s star catalogue ‘Almagest’, recorded in about 137 A.D., and defined the magnitude-intensity relationship on a logarithmic scale. Stellar magnitudes observed with the naked eye recorded in seven old star catalogues were analyzed i...
متن کاملMagnitude systems in old star catalogues
Abstract The current system of stellar magnitudes first introduced by Hipparchus was strictly defined by Norman Robert Pogson in 1856. He based his system on Ptolemy’s star catalogue ‘Almagest’, recorded in about 137 A.D., and defined the magnitude-intensity relationship on a logarithmic scale. Stellar magnitudes observed with the naked eye recorded in seven old star catalogues were analyzed in...
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The comparison of visual magnitudes of stars compiled in old materials is expected to yield informations about their long-term magnitude variations. In seven old catalogues whose philological studies were finished, the sampled stars amount to 2124 except for stars that we could not identify, double stars and known variables. Comparing seven old materials each other, the independency of catalogu...
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ژورنال
عنوان ژورنال: Nature
سال: 1907
ISSN: 0028-0836,1476-4687
DOI: 10.1038/075331a0