NGC 7293 – Helix Nebula

The Helix Nebula, also known as The Helix, NGC 7293, is a large planetary nebula (PN) located in the constellation Aquarius. Discovered by Karl Ludwig Harding, probably before 1824, this object is one of the closest to the Earth of all the bright planetary nebulae. The estimated distance is about 215 parsecs (700 light-years). It is similar in appearance to the Cat’s Eye Nebula and the Ring Nebula, whose size, age, and physical characteristics are similar to the Dumbbell Nebula, varying only in its relative proximity and the appearance from the equatorial viewing angle. The Helix Nebula has sometimes been referred to as the “Eye of God” in pop culture, as well as the “Eye of Sauron”.

The Helix Nebula is an example of a planetary nebula, formed by an intermediate to low-mass star, which sheds its outer layers near the end of its evolution. Gases from the star in the surrounding space appear, from our vantage point, as if we are looking down a helix structure. The remnant central stellar core, known as a planetary nebula nucleus or PNN, is destined to become a white dwarf star. The observed glow of the central star is so energetic that it causes the previously expelled gases to brightly fluoresce.

Imaging telescopes or lenses: Takahashi FSQ130ED
Imaging cameras: Atik 460M
Mounts: Takahashi EM 400 Temma 2M
Guiding telescopes or lenses: Takahashi FS60CB
Guiding cameras: QHY CCD QHY 5 II
Focal extender: Takahashi QE 1.6x
Software: PHD 2, Pleiades Astrophoto PixInsight , Sequence Generator Pro SGP,
Filters: Astrodon 3nm Ha, Astrodon 3nm OIII,
Accessories: Robofocus Focuser, ATIK EFW2
Astrodon 3nm Ha 15 x 1200″
Astrodon 3nm OIII 17 x 1200″
Integration: 10 Hours 40 mins

Autore: Brendan Kinch (sito)