November 21, 2024

M15 – Globular Cluster in Pegasus

M15 – Globular Cluster in Pegasus

Telescope: Light Switch 8 @ f/10, altaz mode

Camera: Stock Canon 600D, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 39x10sec, ISO 1600, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/25sec, Tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency, windy

Lensed Sky Quality Meter: 18.3

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

M15, a bright, condensed globular cluster in a relatively lonely stretch of sky in Pegasus. It is one of the oldest known globular clusters with an estimated age of 13.2 billion years and the first globular cluster found to have a planetary nebula (Pease 1), one of only four planetary nebula associated with a globular cluster. M15 is also one of the most condensed globular cluster and at some point in the distant past it experienced a core collapse that may have heralded the formation of a black hole in its nucleus. This is supported by the fact the M15 is an x-ray source.

This is one of a series of images that I have been taking to explore using relatively simple equipment and techniques. This is one of a short series of images taken with my Light Switch 8 at its native f/10 focal length.

M15 is currently well placed in the south at sunset.