Cometary Globules in the Gum-Vela Complex
Abstract
The characteristics of 29 cometary globules (CGs) in Gum-Vela are described, and the origin of the CGs is discussed. The CGs appear to lie on an annulus of angular radius 11 degrees, and there appears to be a central six degree radius zone in which only one CG is found. The CGs have tails directed away from a common central region, and have a total mass of 100 solar masses. Their velocities are best explained by galactic rotation and related effects. The CG complex can best be modelled by a shell of radius 80 pc or more in which the CGs are distributed in a clumpy fashion. The shell is expanding at up to 5 km/s. The formation of the CGs can be attributed to either Rayleigh-Taylor instability or to the shell impacting dense clouds in the ambient interstellar medium. A complete map of molecular clouds in this region is required to distinguish between the two modes of formation.
- Publication:
-
Astrophysical Letters
- Pub Date:
- 1983
- Bibcode:
- 1983ApL....23..119Z
- Keywords:
-
- Astronomical Models;
- Comets;
- Interstellar Matter;
- Molecular Clouds;
- Astronomical Photography;
- Galactic Rotation;
- Plasma Interactions;
- Stellar Winds;
- Taylor Instability;
- Astrophysics