The Distribution of Extra-Galactic Nebulae

view Abstract Citations (242) References (6) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Distribution of Extra-Galactic Nebulae Hubble, Edwin Abstract The object of the investigation is to determine the distribution of extra-galactic nebulae to a faint uniform limiting magnitude. The material consists of counts of about 4~, 000 nebulae on 1283 plates with the 100-inch and 60-inch reflectors, distributed over the three-quarters of the sky north of ₃Q0 Dec. The counts are reduced to the stand- ard conditions of excellent one-hour exposures at the zenith on Eastman 40 plates with the 100-inch reflector. In general no nebulae are found along the Milky Way. The zone of avoidance, repre- senting local obscuration, is irregular and fol]ows the geheral pattern of the known ob- scuring clouds. It is bordered by partial obscuration, which fades away into the regions of normal distribution where the frequency-curve of log Nm closely approximates a Gaussian error-curve. Systematic variations in longitude are appreciable only in the lower latitudes, where obscuration appears to be conspicuously greater in the direction of the galactic center than in the opposite direction. There is a definite variation with latitude, which from the poles to about j~ = i ~° is represented by the cosecani formul Publication: The Astrophysical Journal Pub Date: January 1934 DOI: 10. 1086/143517 Bibcode: 1934ApJ. . . . 79. . . . 8H full text sources ADS | data products SIMBAD (62) Related Materials (1) Reprint: 1934CMWCI. 485. . . . 1H