This is the Helix Nebula, NGC7293, a large planetary nebula located in the constellation Aquarius. It is just 650 light-years away and thus one of the closest planetary nebulae. It has been expanding for about 50000 years and has reached a diameter of about 2.9 light-years. The small dot in the center is the core of the original star that will evolved further into a white dwarf. The expelled outer shell of the star now forms this stunning nebula, whose atoms emit light in their characteristic transition wavelengths. This is the typical fate of solar-mass stars at the end of their life… and it will be that fate of our Sun in about 5 billion years.
The image is composed from exposures with just two narrowband filters, Hα and OIII, which have been mapped to the red color channel and the blue and green color channels, respectively. The total expose time was only 7 hours with our 17” telescope, but still the faint outer envelope is visible, as well as the intricate structures in the inner part of the nebula. We will come back to this target next season and gather more data 🙂
|Planewave CDK17, D=430mm, f=2940 mm
|QHY600M Full Frame CMOS, 9-Slot Filter Wheel with Baader Filters
|6 hours total, HO 66+55 x 180sec, BIN 2×2
|8 – 24 October 2021
|TURMX @ E-EyE Observatory, Extremadura
|Robert Roth, 31 October 2021