Observer's guide
About NGC 6656
NGC 6656 (M22) is catalogued as a globular cluster in Sagittarius. Its J2000 position is RA 18:36:24.20, Dec -23:54:12.3, corresponding to 279.0998 degrees RA and -23.9047 degrees Dec. The local catalogue places it about 10,100 light-years away. Its referenced angular extent is approximately 24 by 24 arcminutes.
Observing tips
StarWatchr rates this as a very easy target at magnitude 5.1. It is associated with summer observing, with midnight placement typically strongest around June. From 52 degrees north its theoretical meridian altitude is about 14.1 degrees; local horizons and the live altitude chart determine the practical window.
Its brightness makes it a practical binocular or small-telescope candidate when it is well above the horizon.
What to expect
The SIMBAD classification for the matched source is GlC. A published radial velocity value is -147.8 km/s. The SIMBAD record currently connects it to 1471 bibliographic references.
Its roughly 24 arcminute span suits a medium field of view. Use the listed 24 by 24 arcminute extent to check framing, and treat catalogue magnitude as integrated brightness rather than a direct measure of visual contrast.