Observer's guide
About Cocoon Nebula
Cocoon Nebula (C19) is catalogued as an emission nebula in Cygnus. Its J2000 position is RA 21:53:29, Dec +47:16:06, corresponding to 328.372 degrees RA and 47.246 degrees Dec. The local catalogue places it about 3,300 light-years away. Its referenced angular extent is approximately 8.2 by 8.2 arcminutes.
Observing tips
This is rated as a hard target at magnitude 10. It is associated with summer observing, with midnight placement typically strongest around August. From 52 degrees north its theoretical meridian altitude is about 85.2 degrees; local horizons and the live altitude chart determine the practical window.
Because it is faint, use a larger aperture where possible, avoid bright Moon conditions, and use averted vision.
What to expect
The SIMBAD classification for the matched source is OpC. A published radial velocity value is -5.5 km/s. The SIMBAD record currently connects it to 516 bibliographic references.
At roughly 8.2 arcminutes across, it benefits from a narrower field and adequate image scale. Use the listed 8.2 by 8.2 arcminute extent to check framing, and treat catalogue magnitude as integrated brightness rather than a direct measure of visual contrast.