NGC 869
This cluster is rich in hot, blue B-type giants and supergiants, evidence of its very young stellar population. With an estimated age of about 13 million years, it contains several hundred stars packed into a dense core, giving it a noticeably concentrated appearance.
NGC 884
Slightly older, at around 14 million years, NGC 884 is a bit more loosely structured but equally populated with luminous young stars. Its brightest members include blue-white supergiants and a handful of red and yellow evolved stars that contrast with the predominantly blue population.
Image Session Details
-Location: 50.23°N, 8.46°E
-Target: Messier 52 and Bubble Nebula
-Integration: 130 × 90s = 3h 15m
-Camera: Nikon D3500 (APS-C DSLR) – ISO 400
-Telescope: Askar 103 APO + 0.8× reducer (576 mm)
-Mount: Bresser Exos-2 + OnStep
-Control: ASIAIR Mini
-Guiding: SVBONY SV165 + ASI120MM Mini
-Sky Quality: Bortle 4, SQM ~20.8
-Moon Phase: Waxing Gibbous (~61%)
-Filter: None (stock DSLR)
-Date: 01Octomber 2025
-Object Type: Globular Cluster + Planetary Nebula
-Constellation: Cassiopeia
-Apparent Size: ~15′ × 8′
-Distance: ~7,100–7,500 ly (≈2.2–2.3 kpc)
General Properties
Coordinates: RA 23h 20m 48s, Dec +61° 12′ 06″
Apparent Magnitude: ~10
Angular Size: ~15′ × 8′
Distance: ~7,100–7,500 ly (≈2.2–2.3 kpc)
Constellation: Cassiopeia
Discovery: William Herschel, 1787
Scientific Databases
[ POSITION ]
RA: 350.201200°
Dec: +61.201700°
[ PHOTOMETRY ]
IRAS 12 µm: 28.50 Jy
IRAS 25 µm: 182.00 Jy
IRAS 60 µm: 433.00 Jy
IRAS 100 µm: 313.00 Jy
1.4 GHz flux: 0.59 Jy
[ DISTANCE ]
388.73 pc (1.27 kly, Gaia proxy hot-star parallax)
~2.2–2.3 kpc (7.1–7.5 kly, nebula literature consensus)
[ PROVENANCE ]
Gaia DR3: source_id 2014149588055625984, G=6.91, BP−RP=0.05, π=2.572±0.025 mas
[ ALIASES ]
Bubble Nebula, LBN 548, NGC 7635, NGC7635, SH 2-162
-NED
Observation Notes
-Photographic Magnitude: 9.0
