The superfluous asterism, named Abhijit, included the bright star a Lyrae, under whose influence the gods had vanquished the Asuras.
There are several wellmarked varieties of short-period variables; the most important are typified by the stars Algol, # Lyrae, Geminorum and S Cephei.
The variable star Lyrae, which is typical of another class, was also discovered by Goodricke in 1784.
No hard and fast physical distinction can be drawn between the various classes of short-period variables; as the distance between the components diminishes the Algol variable merges insensibly into the (3 Lyrae type.
A continuous gradation can be traced from the most widely separated visual binaries, whose periods are many thousand years, to spectroscopic binaries, Algol and # Lyrae variables, whose periods are a few hours and whose components may even be in contact, and from these to dumb-bell shaped stars and finally to ordinary single stars.