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The Cocoon Nebula in HaRGB
David Cruz · Astromidnight
In Cygnus, the Cocoon Nebula glows red at the end of a long trail of dark dust, Barnard 168. Inside it, a young and very hot star lights up the gas it was born from.
| Catalogue | IC 5146 · Sh2-125 · LBN 424 |
| Type | Emission and reflection nebula with a young cluster |
| Distance | ≈ 2,650 light-years |
| Field | 134.3′ × 86.2′ |
| Real width | ≈ 104 × 67 light-years |
| Scale | 0.90″ / pixel |
| Orientation | −161° · south up |
| RA (centre) | 21h 50m 12s |
| DEC (centre) | +47° 27′ 24″ |
| Constellation | Cygnus |
| Objects in field | IC 5146 · B 168 · 5 LDN · vdB 147 · V1735 Cyg |
Distance to the Cocoon from the Gaia parallaxes of the nebula's young stars: 813 ± 106 pc (Wang et al. 2019). The real width assumes that distance; the dark clouds of the tail may lie between 600 and 800 pc, so it is approximate. Distances to vdB 147 and V1735 Cyg from Gaia parallax (SIMBAD). Positions of all objects taken from SIMBAD; those of the dark nebulae are the catalogue centre, which is approximate.
39 h 34 min of light
Each tick is one exposure. 542 in total, with the camera at −10 °C and gain 100. Calibrated with 50 darks, 50 flats and 50 bias. The Moon stayed below 80 % illumination throughout.
TS-Optics 150mm/6" ONTC f/4 Newtonian (carbon tube)
ZWO ASI2600MC Pro
ZWO AM5
ZWO ASI120MM Mini
TS-Optics Maxfield .95X Coma Corrector · ZWO EAF
Player One Anti-Halo Pro Dual-Band Ha+OIII Filter 2"
Adobe Photoshop · Pleiades Astrophoto PixInsight · ZWO ASIAIR
São Pedro da Gafanhoeira, Évora · 358 m
Bortle 3