The Variation of the Light from the Night Sky and its Effect
Abstract
Observations have been made with a photoelectric photometer using a potassium photoelectric cell, and they show irregular variations, through the night, in the intensity of the light from the sky in the region of the North Pole. Also, there are variations from night to night which are quite large. Computations have been made of the limiting magnitude of nebulae which could be observed, taking into consideration the variation of the sky brightness with respect to zenith distance, the zodiacal light, and the Milky Way. It is concluded that the limiting magnitude of a nebula is a function of the position with respect to the zenith, the zodiacal light, and the Milky Way, and also with respect to time. For precise photometry of faint nebulae it is necessary to determine the brightness of the sky background by calibration with stars in the field at the time the photograph is being made
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 1937
- DOI:
- 10.1086/143887
- Bibcode:
- 1937ApJ....86..562E