B1900.0
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(Redirected from 1900.0)
The B1900.0 epoch is used in astronomy.
Since the right ascension and declination of stars are constantly changing due to precession, astronomers always specify these with reference to a particular epoch. This standard was superseded by the succeeding epoch, B1950.0. The current one in standard use is the J2000.0 epoch.
The "B" in the prefix indicates that it is a Besselian epoch, as opposed to a Julian epoch.
