Flamsteed designation

A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England. They are named after John Flamsteed, author of the Historia Coelestis Britannica, the first major star catalogue compiled with the aid of a telescope. Flamsteed’s own catalogue did not include what are now known as Flamsteed numbers, but its listing of stars in each constellation provided the basis for later astronomers to add them.