A Study of the Orion Aggregate of Early-Type Stars.
Abstract
A catalogne of spectroscopic and photoelectric observations of 190 members of the Orion aggregate is given. The photoelectric observations were made with the 82-inch and 13-inch reflectors of the McDonald Observatory; the spectrograms were taken with the 40-inch refractor of the Yerkes Observatory. A spectroscopic distance modulus of 8.5 mag. was obtained for the aggregate. This material has also made possible an investigation of the anomalous reddening in Orion, the absolute magnitudes of the 0-type stars associated with the aggregate, and the radial distribution of color excess within the Orion Nebula. The high ratio of total to selective absorption found by Baade and Miakowski for the Trapezium stars is found to apply also to other reddened stars in the aggregate; however, their hypothesis of a transparent region in the center of the nebula is not confirmed. The correlation between reddening and the diffuse interstellar features in the spectra of the Orion stars is discussed.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 1952
- DOI:
- 10.1086/145610
- Bibcode:
- 1952ApJ...116..251S