A large, cold and unusual molecular cloud in Monoceros.
Abstract
Observations of the J = 1 tends to 0 rotational transition of CO near the galactic plane in Monoceros (1 is approximately equal to 216 deg) reveal a molecular cloud with unusually low peak CO temperatures (less than 2 K) but wide lines (about 7 km/s) typical of much warmer clouds. At the assumed distance of 3 kpc, the cloud is large (250 x 100 pc), has a mass of 7-11 x 10 to the 5th solar masses, and is well removed from the galactic midplane (130 pc). Except for a possible H II region, all the signs of star formation usually shown by clouds of comparable mass are missing. The cloud, unlike cloud complexes of similar size, is a single, continuous object that apparently has not been torn apart by star formation. Clouds with such properties are rare in the Galaxy; only one or two similar objects have been found. The possibility that the cloud is young and not yet forming stars but will evolve into a typical cloud complex once star formation begins is discussed.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1985
- DOI:
- 10.1086/163291
- Bibcode:
- 1985ApJ...294..231M
- Keywords:
-
- Astronomical Spectroscopy;
- Molecular Clouds;
- Carbon Monoxide;
- H Ii Regions;
- Molecular Spectra;
- Radio Spectra;
- Stellar Evolution;
- Astrophysics