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Although no longer in serious use, mention should be made of Ptolemy's star catalogue published in the 2nd century as part of his Almagest, which lists 1,022 stars visible from Alexandria. It was the standard star catalogue in the Western and Arab worlds for over a thousand years. Ptolemy's catalogue was based to some extent on an earlier one by Hipparchus from the 2nd century B.C. An even earlier star catalogue was that of Timocharis of Alexandria, which was written about 300 B.C. and later used by Hipparchus.
Two systems introduced in historical catalogues remain in use to the present day. The first system comes from Bayer's Uranometria and is for bright stars. These are given a Greek letter followed by the genitive case of the constellation in which they are located; examples are Alpha Centauri or Gamma Cygni . See Bayer designation for more information. The major problem with Bayer's naming system was the number of letters in the Greek alphabet. It was easy to run out of letters before running out of stars needing names, particularly for large constellations such as Argo NavisArgo Navis (or simply Argo was a large southern constellation representing the Argo the ship used by Jason and the Argonauts in Greek mythology. It is the only one of Ptolemy's list of 48 constellations which is no longer officially recognised as a conste.
The second system comes from John FlamsteedJohn Flamsteed ( 19 August, 1646 31 December, 1719) English astronomer, was born in Denby, Derbyshire, England. He was ordained deacon and was preparing to take up a living in Derbyshire, when he was invited to London. On March 4, 1675, he was appointed b's Historia coelestis Britannica . It kept the genitive-of-the-constellation rule for the back end of his catalog names, but used numbers instead of the Greek alphabet for the front half. Examples include 61 Cygni61 Cygni is a star in the Cygnus constellation. Though it is among the least conspicuous of stars visible in the night sky to an observer without an optical instrument, 61 Cygni attracted the attention of astronomers due to its large proper motion. The st and 47 Ursae Majoris47 Ursae Majoris (also called HD 95128 is a yellow dwarf star ( spectral type G0V), similar to our own Sun. It was recently shown to possess two large planets. 44 Ursae Majoris is 44 light years from Earth in the constellation of Ursa Major. The Planets 4; see Flamsteed designationFlamsteed designations for stars are similar to Bayer designations, except that they use numbers instead of Greek letters. Each star is assigned a number and the Latin genitive of the constellation it lies in. The numbers were originally assigned in order for more information.