Bayer-Flamsteed Designations

When you point at a star in Sky View Café, often you'll see a code like "37 Gam Cyg", "19 Bet Ori" or "6 Alp-2 Cap" in the marquee. This is a shorthand notation for the Bayer-Flamsteed designations of the stars. The first number, if present, is the Flamsteed designation for a given star, which numbers the brighter, visible stars in a constellation in a sequence from west to east by right ascension. For example, "1 Kap Lyr" is the westernmost major star in the constellation Lyra.

The three-letter code, which, if given, precedes the code for a star's constellation, is an abbreviation of the name of a Greek letter -- the Bayer designation for a star. Bayer ranked the stars (not always precisely) by brightness, with the alpha star typically being the brightest in a given constellation, beta the second brightest, and so on, down through the Greek alphabet. If a star is a double star, a -1 or -2 is used after the Greek letter to distinguish between the two stars.

The last three-letters signify the constellation in which a star appears (see the list below). Without getting deeply into the intricacies of Latin grammar, when you read this style of star designation, you use the "genitive" form of the constellation name. For example the brightest star in the constellation Lyra, Vega, also goes by the designation "3 Alp Lyr", read "three alpha Lyrae". [back]