Photometric standard stars

Photometric standard stars are a series of stars that have had their light output in various passbands measured very carefully. Other objects can be observed using CCD cameras or photoelectric photometers connected to a telescope, and the flux, or amount of light received, can be compared to a photometric standard star to detrmine the exact brightness, or stellar magnitude, of the object.

The current set of photometric standard stars most often used by astronomers is that published by Arlo U. Landolt in 1992 in the Astronomical Journal, vol. 104, no. 1, p. 340-371.