NGC 6820 & NGC 6823 (Vulpecula)
The emission nebula NGC 6820 and the open cluster NGC 6823 in the constellation Vulpecula
Fig. 1 - A cosmic cradle in Vulpecula: The emission nebula NGC 6823 and the open cluster NGC 6823 in the constellation Vulpecula, photographed with an 8-inch f/4 Newtonian reflector on a ZWO AM5 mount.
| Object name: | Constellation: | Coordinates: | Apparent size: | Visual brightness: |
|---|---|---|---|---|
| NGC 6820 | Vulpecula | 19h42m / +23°05' | 60' × 25' | - |
| NGC 6823 | Vulpecula | 19h43m / +23°18' | 7' | 7.1 mag |
NGC 6820 and NGC 6823 form a star-forming complex in the constellation Vulpecula. NGC 6823 is a young open star cluster of approximately 80 bright and faint stars of magnitude 8-13 in an area of about 7', embedded within the emission nebula NGC 6820, which is faint and challenging to observe visually.
The bright, hot stars of the cluster illuminate and shape the surrounding gas, creating a rich field of glowing hydrogen clouds, dark dust lanes, and sculpted pillars reminiscent of the famous Pillars of Creation in the Eagle Nebula. The nebula is part of the much larger H II region Sharpless 2-86 (Sh2-86), an extensive complex of ionized hydrogen that spans an area of approximately 60' × 25'.
NGC 6823 is dominated by massive O- and B-type stars that formed only a few million years ago. The cluster forms the core of the Vulpecula OB1 association, a vast grouping of young, massive stars .
The entire nebular complex has a diameter of approximately 70 light-years and lies about 6,000 light-years from Earth. The central open cluster NGC 6823 itself is about 50 light-years across. Recent measurements by the Gaia mission have enabled astronomers to identify cluster members through their common parallaxes and proper motions. The most probable members of NGC 6823 show parallaxes of roughly 0.35-0.55 milliarcseconds, corresponding to distances between about 6,000 and 9,000 light-years.
The cluster was discovered in 1785 by the German-British astronomer William Herschel, while the nebula NGC 6820 was discovered in 1864 by the German astronomer Albert Marth.
Technical Details:
Exposure time: 7h 9min (143x3min)
Gain: 100
Temperature: -10°C
Date: July 11/12 and July 12/13, 2026
Processing: Astro Pixel Processor (APP) and Photoshop
Calibration: Darks, flats, and bias
Equipment:
Cooled ASI 2600MC Pro camera, TeleVue Paracorr Type II coma corrector, 8" f/4 "ONTC" Newtonian telescope, ZWO AM5 Strain Wave Mount, ZWO OAG-L off-axis system, ASI 174MM Mini guide camera, ASIAIR Plus
Fig. 2 - Search chart for NGC 6823 (and NGC 6820). Copyright 2026 'The Mag-7 Star Atlas Project', www.siaris.net.