IC 1396

The Elephant Trunk Nebula is a concentration of interstellar gas and dust in a region of ionized gas much larger than the trunk itself. It is located in the constellation Cepheus about 2,400 light-years from Earth.

Too faint to be visible to the naked eye, this nebula is one of the most beautiful. Its impressive size of 120 to 150 light-years corresponds to 1,500 stellar systems and 2,000 stars (our own solar system has only one star for comparison).

This nebula allows the creation of new stars thanks to matter, this gas which is mainly hydrogen illuminated by the ionization due to the very energetic radiation of young stars, which, in certain more opaque areas, collapse locally in the form of "Bok globules" and constitute stellar protosystems. These globules, with a mass of about 10 to 40 solar masses and spread over a surface area of about 1 light year, result in the creation of one or more stars.

The image presented here was captured in SHO, that is to say using the palette used by the Hubble telescope. This is created using filters that only allow certain wavelengths of light to pass through (between 3 and 6nm in general) and which correspond to the atoms of ionized hydrogen (Ha), triply ionized oxygen (OIII) and sulfur (SII). By subsequently combining these three layers into a single image, we obtain a photograph allowing us to see the atomic constitution of the nebula. Indeed, the human eye is not able to discern these particular frequencies of light and without this the nebula simply appears in red/pink tones.

Equipment used:
- Skywatcher 80ed Evostar
- ZWO 533mc pro
- ZWO 120mm mini
- EQM-35 Pro
- Asiair plus
- EFW
- EAF
- OAG
- L-Ultimate filter for Ha and OIII layers
- SII filter
- Stacked and Ha/OIII extracted with Siril
- Mosaic created with PixInsight
- Processed with PixInsight
- Finished with Lightroom