NGC 7789 (Cassiopeia)
Fig. 1 - Impressive in any size telescope: The open cluster NGC 7789 in the constellation Cassiopeia, photographed with an 8-inch f/5 Newtonian reflector on a ZWO AM5 mount.
| Object name: | Constellation: | Coordinates: | Apparent size: | Visual brightness: |
|---|---|---|---|---|
| NGC 7789 | Cassiopeia | 23h57m / +56°43' | 16' | 6.7 mag |
The open cluster NGC 7789 ("Caroline's Rose", "Caroline's Haystack", "White Rose Cluster") in the constellation Cassiopeia. The cluster contains up to 15,000 stars, is approximately 8,000 light-years from Earth and has a diameter of 65 light-years. With an estimated age of 1.5 billion years, it is older than most of its kind. Through a telescope, the loops of stars and dark lanes look like the swirling pattern of rose petals as seen from above. NGC 7789 was discovered by Caroline Herschel in 1783 (source: Wikipedia).
Ninety-six 3-minute exposures (288 minutes total exposure) at gain 100 and -10°C, taken on November 9 / 10, 2024 and on November 29 / 30, 2024, were added for this shot with Astro Pixel Processor (APP) software and the final image processing was done in Photoshop. Darks, flats, bias and darkflats were used.
Equipment: Cooled ASI 2600MC Pro camera, TeleVue Paracorr Type II coma corrector, 8" f/5 "ONTC" Newtonian telescope riding on a ZWO AM5 Strain Wave Mount, ZWO OAG-L off axis system, ASI 174MM Mini guide camera, ASIAIR Plus.
Fig. 2 - Search chart for NGC 7789. Copyright 2024 'The Mag-7 Star Atlas Project', www.siaris.net.