The Elephant’s Trunk Nebula

The Elephant’s Trunk is the name given to this small part of the giant IC1396 gas cloud, which is glowing in the radiation from a very bright triple-star system of O-type stars (HD206267), which is out of sight to the left of the field.

O stars are among the hottest and most massive, with surface temperatures between 25,000 and 50,000K. The stellar winds from these stars can be seen to be ionizing the dark clouds in this image, causing their edges to glow brightly. The winds are also powerful enough to strip any proto-planetary disks from around the other stars in the nebula. Hence the stars in IC1396 are not likely to form many planets.

This view combines a standard set of LRGB exposures with a deep H-alpha narrowband image, which provides most of the red ionized hydrogen component.

The field of view in this image is 49 arc-minutes square. South is up.

Exposure times: Luminosity 13hrs, Red 7.5hrs, Green 9hrs, Blue 9hrs, H-alpha 27hrs.

Equipment: Planewave CDK-14 corrected Dall-Kirkham scope, FLI Proline P09000 CCD camera, Astrodon E-series broadband filters and 3-nm Hydrogen-alpha filter. Autoguided using a Monster MOAG off-axis guider and Starlight Xpress UltraStar Pro guide camera.

Acquisition software: Maxim DL, ACP Expert Scheduler. Image processing: Pixinsight.