NGC 7789 in Cassiopeia, Caroline's Rose

NGC 7789, the White Rose Cluster or Caroline's Rose

named after its discoverer, Caroline Herschel.

Hover over the picture for an annotated version

Date:  25 August 2025

FOV:  cropped to 30' × 20'

the angular size of NGC 7789 is about 16'

Rotation:  0.012°

Telescope:  Stellarvue SVX102T + SFFX-1 flattener (714mm, f/7)

Guiding:  ZWO ASI120MM mini mono guide camera,

Stellarvue F050G 50mm guide scope

Computer:  ASIair pro Raspberry Pi

Mount:  ZWO AM5

Camera:  ZWO ASI6200MC APS/c Pro Cooled (-10°C)

color CMOS in APS/c mode with gain 100

Resolution:  1.053 arcsec/pixel

Pixel size:  3.76 µm

Filter:  Optolong UV/IR

Stacking:  thirty-four 240 second frames using PixInsight

Calibration:  20 dark, 20 flat, 20 dark flat

Total Time:  2 hours 16 minutes

Processing:  Pixinsight – SPCC, DBE, SPCC, BlurXT, NoiseXT,

MultiscaleAdaptiveStretch, Sat, DynCrop/Scale

Location:  Darling Hill Observatory near Vesper, NY