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7 brightest stars visible to the naked eye from Earth and their significance
When we observe the stars in the night sky, their brightness can be pretty dramatic, but the way astronomers measure ...
PBS8 年
Leavitt discovers a correlation between Cepheids' period and luminosity
The brighter the star is overall, the longer the period ... in 1912 -- in a chart of 25 cepheid periods and their apparent brightness. Using this, astronomers only needed to know the period ...