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"Alpha Centauri", "Gamma Cygni" or "Mu Cephei". Flamsteed numbers also refer to slightly dimmer stars; they consist of a number followed by a constellation, such as "40 Eridani" or "61 Cygni". Click on this option and you get a list of the 88 constellations. Select one and you will get a list of Bayer and Flamsteed objects in that constellation. (Bayer objects have a Flamsteed number as well.) Click on the star you want to recenter on it. The brighter stars have names, sometimes handed down from ancient civilizations: Betelgeuse, Sirius, Capella, Antares, and so on. Clicking on the "Common Name" option brings up a list of over 290 common names for stars. When you find the star you want, click on it and Guide will redraw the chart centered on that star. A number of catalogs are described below. For each of these catalogs, click on the catalog name and enter the designation and Guide will recenter on the star. The "Nearby Star" option will bring up a list of nearby stars. Many of these have odd names such as "Proxima Centauri", "Barnard's Star", or "Kruger 60", that won't appear in any of the standard catalogs. This function can be especially useful in such cases. The Yale (Bright Star) Catalog or HR catalog lists 9,096 stars. The information in it is mostly of interest to professionals and gung-ho amateurs. The SAO (Smithsonian Astronomical Observatory) catalog lists more (258,997) stars but has less information per star than the Bright Star Catalog. Astronomy magazines will often define a star by its SAO number. The more recent PPM (Position and Proper Motion) catalog lists slightly more stars than the SAO catalog. It was intended as a more accurate replacement for the SAO. The HD (Henry Draper) catalog, compiled early in the 1900s, lists over 359,000 stars. The "Guide Star" option lets you find a star by Hubble Guide Star Catalog number. The GSC lists over 15 million objects, but only provides a star's location and brightness (or astronomical magnitude. See page 75). A GSC designation consists of a zone number (between 1 and 9537) and a star number within that zone, usually (but not always) less than 10000. Many variables are designated by one or two letters and a constellation, like R Coronae Borealis (R CrB) or UV Ceti (UV Cet). The rules used for these designations allow 334 designations of this type per constellation; further variables are given a number following a V. Thus, V335 Ori is the first variable found in Orion after letter designations were exhausted.
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