The Double Cluster of Perseus is a pair of very bright open clusters, visible in the homonymous constellation of Perseus; they are also known as h and χ Persei or NGC 869 and NGC 884.
Both clusters are found in the Arm of Perseus, the spiral arm of the Milky Way immediately outermost from ours, the Arm of Orion.
In the image shown here, NGC 869 is the cluster in the upper part, while NGC 884 is the one in the lower part; their distance is 6800 light years and 7600 light years respectively.
Technical dataOptic TS Optics 76 EDPH - Aperture 76mm, focal lenght 342mm, f/4.5Mount Skywatcher EQ6RCamera ZWO ASI 294MM Pro with external filter wheel 7 positionsFilters Antlia 36mm RGBGuiding system Artesky Ultraguide 32mmExposure details R 20x120" bin2 -15C G 20x120" bin2 -15C B 20x120" bin2 -15C
Gain 120, offset 30
Total integration 2hAcquisition Voyager, PHD2Processing Pixinsight 1.8, Photoshop CS5SQM-L 21.2 Location Promiod (Aosta Valley, Italy)Date 7 November 2021