| Date 2015/06/16 Observation place My permanent observatory in Longueuil in white light pollution zone |
Technical
| Telescope | Orion 80ED refractor - Diameter 80mm, focal length 480mm, f / 6 |
| Mount | Celestron CGEM |
| Imaging camera | Atik 383 L + monochrome regulated at -20o Celsius |
| Autoguiding camera | ZWO ASI 120MM in parallel with the Orion Mini Guider |
| Auto Guidance Accuracy (RMS) | 1,55 '' of arc (3,1 '' of arc in total) |
| Image type | Ha + OIII (Ha-OIII-OIII) Luminance image with Ha and OIII filters |
| Exhibition | Ha (11 x 10 'bin 2 × 2), OIII (11 x 10') |
| Image acquisition software | Maxim DL |
| Guidance software | PHD Guiding 2 |
| Pretreatment | Maxim DL |
| Treatment | Photoshop and PixInsight |
Object description
| Object type | Emission nebula "The Witch's Broom Nebula" |
| Constellation | Swan |
| Visual magnitude | +5 |
| Distance | 1500 light years |
| Dimension seen from Earth | 70 x 6 arc minutes |
| NGC6960 is nicknamed the Witch's Broom Nebula. It is part of a vast cloud of gas and dust, called the Swan Veil Nebulae, listed by several nebulae. It is referred to as the Little Swan Lace or the Witch's Broom Nebula. The NGC6960 nebula is not visible in a small telescope because it is very dark. To see it in a telescope with a large diameter (8 '' and more), you need a sky that is very little polluted by city lights. Also since it is very dark, it is difficult to photograph. It takes a long exposure time per photo and the integration of several images. To bring out the beautiful red and blue tones of the nebula in this significant light pollution site, I used the Ha (for the red color) and OIII (for the blue color) filters. In addition, they effectively filter the light caused by light pollution while allowing more than 95% of the light signal of the nebula. I also managed to bring out the beautiful nebulosities at the bottom of the nebula, which is amazing considering the extreme light pollution at the site. The veil nebulae, of which NGC6960 is a part, represent the remains of several exploded supernovas. A remnant of supernovae is the final evolutionary state of a massive star (more than 6 times the mass of the Sun) that ends its existence with a huge explosion. After the explosion, only a rapidly expanding cloud of gas remains surrounding the star's residue. This gigantic gas cloud (of which we see only a part) is conducive to the formation of future planets. The stars which surround it go by gravity, appropriate these gases and dust. This dust will then orbit around these stars. Subsequently, this dust will assemble by gravity to form future planets. It is a superb anthill for the creation of planets. Perhaps, one of them will be conducive to the creation of life! |
| Richard Beauregard Sky Astro - CCD My impression "We cannot be alone in this gigantic universe" |