September 23, 2024

NGC 7789 – Open Cluster in Cassiopeia

NGC 7789 – Open Cluster in Cassiopeia

Telescope: Light Switch 8 @ f/6.2 (Optec 0.62x focal reducer), altaz mode

Camera: Full Spectrum Modified Canon 600D, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 40x10sec, ISO 1600, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/10sec, Tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, fair transparency

Lensed Sky Quality Meter: 18.5

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

NGC 7789 is a large and wonderfully rich open cluster located just west of Cassiopeia. It was discovered by Caroline Herschel in 1782 and is sometimes called Caroline’s Rose. It is a delicate object in small to moderate scopes, but blossoms into a rich field in large telescopes. When viewing this cluster I like to spend some time with the field. At first all I will see are the foreground stars and perhaps a soft glow in the background. As my eye adjusts, the first faint stars appear, and then it slowly blooms into a beautiful patch of stardust.

NGC 7789 is currently high in the northeast after sunset.