The Majestic Double Cluster in Perseus. NGC 869/NGC 884
The Double Cluster (also known as Caldwell 14) consists of the open clusters NGC 869 and NGC 884 (often designated h Persei and χ Persei, respectively), which are close together in the constellation Perseus. Both visible with the naked eye, NGC 869 and NGC 884 lie at a distance of 7,500 light years.
NGC 869 has a mass of 3,700 solar masses and NGC 884 weighs in at 2,800 solar masses; however, later research has shown both clusters are surrounded with a very extensive halo of stars, with a total mass for the complex of at least 20,000 solar masses. Based on their individual stars, the clusters are relatively young, both 12.8 million years old. In comparison, the Pleiades have an estimated age ranging from 75 million years to 150 million years.
There are more than 300 blue-white super-giant stars in each of the clusters. The clusters are also blueshifted, with NGC 869 approaching Earth at a speed of 39 km/s (24 mi/s) and NGC 884 approaching at a similar speed of 38 km/s (24 mi/s). Their hottest main sequence stars are of spectral type B0. NGC 884 includes five prominent red supergiant stars, all variable and all around 8th magnitude: RS Persei, AD Persei, FZ Persei, V403 Persei, and V439 Persei. (Wikipedia.org)
Technical Information for This Image
This image was taken with a William Optics Zenithstar 81 APO Doublet Refractor on an iOptron CEM25P mount. The main imaging camera, attached to the prime focus of the telescope was a ZWO ASI294MC Pro cooled camera which was cooled to -5C. The 27 exposures were each 120 seconds at Bin 1x1.
The gain was set to 120. Auto guiding was done using a William Optics 50mm guide scope with a 200mm FL. Attached to the guide scope was a ZWO ASI290MC camera which was connected to PHD2 autoguiding software. Capturing was done with Astrophotography Tool (APT) software and post processed with Pixinsight software with finishing touches put in using Adobe Photoshop Creative Cloud. Polar Alignment for the evening was done using SharpCap software.
The Majestic Double Cluster in Perseus. NGC 869/NGC 884
The Double Cluster (also known as Caldwell 14) consists of the open clusters NGC 869 and NGC 884 (often designated h Persei and χ Persei, respectively), which are close together in the constellation Perseus. Both visible with the naked eye, NGC 869 and NGC 884 lie at a distance of 7,500 light years.
NGC 869 has a mass of 3,700 solar masses and NGC 884 weighs in at 2,800 solar masses; however, later research has shown both clusters are surrounded with a very extensive halo of stars, with a total mass for the complex of at least 20,000 solar masses. Based on their individual stars, the clusters are relatively young, both 12.8 million years old. In comparison, the Pleiades have an estimated age ranging from 75 million years to 150 million years.
There are more than 300 blue-white super-giant stars in each of the clusters. The clusters are also blueshifted, with NGC 869 approaching Earth at a speed of 39 km/s (24 mi/s) and NGC 884 approaching at a similar speed of 38 km/s (24 mi/s). Their hottest main sequence stars are of spectral type B0. NGC 884 includes five prominent red supergiant stars, all variable and all around 8th magnitude: RS Persei, AD Persei, FZ Persei, V403 Persei, and V439 Persei. (Wikipedia.org)
Technical Information for This Image
This image was taken with a William Optics Zenithstar 81 APO Doublet Refractor on an iOptron CEM25P mount. The main imaging camera, attached to the prime focus of the telescope was a ZWO ASI294MC Pro cooled camera which was cooled to -5C. The 27 exposures were each 120 seconds at Bin 1x1.
The gain was set to 120. Auto guiding was done using a William Optics 50mm guide scope with a 200mm FL. Attached to the guide scope was a ZWO ASI290MC camera which was connected to PHD2 autoguiding software. Capturing was done with Astrophotography Tool (APT) software and post processed with Pixinsight software with finishing touches put in using Adobe Photoshop Creative Cloud. Polar Alignment for the evening was done using SharpCap software.