Submillimeter Observations of the Orion Nebula and NGC 2024
Abstract
We report here new observations at submillimeter wavelengths ( 4O0 ) of the Orion Nebula and NGC 2024. These observations provide a fairly detailed (FWHM 1 6) map of the Orion Nebula at these wavelengths. We attribute the Orion Nebula emission to optically thin thermal radiation from dust grains in the molecular cloud with peak emission centered on the KL source. A comparison of our data with those of Harvey et a'. at longer wavelengths shows that the emissivity must vary as . We find evidence that the dust temperature varies with position, with the center having the higher temperature. If optical constants determined from lunar silicate material are used, then 0.05A).10 g of small particles would be required to produce the observed submillimeter emission, but this suggests a far larger mass ( 5 X 102 M0 in the central 1 6) in the Orion molecular cloud than is normally assumed. Alternatively, the data require an opacity at 100 greatly exceeding that of the lunar silicates. Subject headings: infrared - Orion Nebula - photometry
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1974
- DOI:
- 10.1086/181555
- Bibcode:
- 1974ApJ...191L..83S