Blinking Planetary Nebula

Blinking Planetary Nebula

About this image

NGC 6826 — The Blinking Planetary Nebula

NGC 6826, also known as Caldwell 15 or the Blinking Planetary Nebula, is a small planetary nebula in the constellation Cygnus. Despite the name, a planetary nebula has nothing to do with planets. It is the glowing shell of gas thrown off by a dying Sun-like star near the end of its life.

At the centre of NGC 6826 is a bright white dwarf, the exposed core of the original star. Around it is a delicate shell of gas and dust, pushed outward into space and lit up by the intense radiation from the hot central remnant. In images, this gives the nebula its compact, eye-like appearance.

The “blinking” nickname comes from how it appears visually through a telescope. When you look directly at it, the bright central star can dominate the view, making the surrounding nebula harder to see. Look slightly away using averted vision, and the faint outer glow seems to pop back into view.

NGC 6826 is around 2,200 light-years away and is thought to be a young planetary nebula, roughly a thousand years old. It is a tiny object in the sky, but it is a fascinating reminder of what may eventually happen to stars like our Sun: the outer layers drift away, leaving behind a small, hot stellar core surrounded by a glowing bubble of gas.

This was a challenging but rewarding target to image. Its small size means it needs good tracking, careful focus and enough focal length to bring out the structure. The result shows a beautiful little remnant of stellar death.

Annotated image

Image details

Equipment

Acquisition

Observation notes

Happy with the result, considering the light evening and the new setup

Processing notes

Stacking using Astro Pixel Processor. In order to show detail in the core, I played around with masks so I could stretch the image whilst protecting the core.

Posted from CityAstroLog.