WhatTheStar

Field guide · Stars

Star

Star names and designations

Most bright stars have an old name, usually Arabic, and a Greek letter plus their constellation — Betelgeuse is also α Orionis.

Proper names
Mostly Arabic, some Greek and Latin
Bayer letters
α, β, γ… + constellation (1603)
Flamsteed numbers
61 Cygni, 51 Pegasi

The traditional names mostly came to Europe from Arabic astronomy, which had in turn inherited Ptolemy’s Greek catalogue. So many are descriptions: Betelgeuse is garbled from “the hand of al-Jawzā”, Deneb means “tail”, Fomalhaut is “the mouth of the fish”.

In 1603 Johann Bayer gave the brighter stars of each constellation Greek letters, roughly in order of brightness, with the constellation’s Latin genitive: α Orionis, β Persei. John Flamsteed later numbered them from west to east — 61 Cygni. Fainter stars are just catalogue numbers.

Since 2016 the International Astronomical Union has kept an official list of proper names, and has added names from other cultures to it — Hawaiian, Chinese, Aboriginal Australian and more.

See it in the sky

Each one opens the sky map pointed at it, for tonight, from where you are.

Related

All field-guide entries · Open the sky map

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