Accession Number : AD0445094

Title :   SPECTROPHOTOMETRY OF GALACTIC NEBULAE ORION NEBULA II,

Corporate Author : HAMBURGER STERNWARTE (GERMANY F R)

Personal Author(s) : Wurm, K.

Report Date : 01 JUN 1963

Pagination or Media Count : 41

Abstract : It is shown that the so called emission measure of diffuse nebulae for more extended emission layers has to be replaced by another expression, which takes account of the extinction originating from dust particles. The new formula explains the observation, that in the Orion-nebula the surface brightness in the Balmer lines is always directly proportional to the electron densities measured at different points of the surface of the nebula. Dark spots in bright nebulae can appear in consequence of clouds having smaller densities but more extended depths than their surrounding clouds. Arguments are brought forward in favor of the conception that also the well known 'globules' and 'bright-rim structures' in nebulae have to be explained in this way and do not represent volumes of particular high densities. (Author)

Descriptors :   *GALAXIES, BRIGHTNESS, NEBULAE, ELECTRON DENSITY, SPECTROPHOTOMETERS.

Distribution Statement : APPROVED FOR PUBLIC RELEASE