CG4
Cometary globules are isolated, relatively small clouds of gas and dust within the Milky Way. This example, called CG4, is about 1,300 light years from Earth. Its head is some 1.5 light-years in diameter, and its tail is about eight light-years long. The dusty cloud contains enough material to make several Sun-sized stars. The head of the nebula is opaque, but glows because it is illuminated by light from nearby hot stars. Their energy is gradually destroying the dusty head of the globule, sweeping away the tiny particles which scatter the starlight. This particular globule shows a faint red glow from electrically charged hydrogen, and it seems about to devour an edge-on spiral galaxy (ESO 257-19) in the upper left. In reality, this galaxy is more than a hundred million light-years further away, far beyond CG4.
| Observatory: | Cerro Tololo Inter-American Observatory Cerro Tololo, Chile |
|---|---|
| Telescope: | CTIO 4-Meter |
| Instrument: | Mosaic II |
| Astronomer: | T.A. Rector (University of Alaska Anchorage) and T. Abbott (NOAO/AURA/NSF) |
| Date of Observation: | 11-09-2005 |
| Filters and Assigned Colors: | B (blue), V (green), I (orange) and Hydrogen-Alpha (red) |
| Exposure Times: | 5x5min for BVI, 5x10min for H-alpha |
| Location of Image: | Puppis |
| Field of View: | 36.0 x 24.0 arcmin |
| Orientation: | North is up, East is to the left |
| Link to Larger Image | |
| Link to Full Resolution Image | |
| © Copyright Statement |