Observer's guide
About NGC 6809
NGC 6809 (M55) is catalogued as a globular cluster in Sagittarius. Its J2000 position is RA 19:39:59.40, Dec -30:57:43.5, corresponding to 294.9988 degrees RA and -30.9647 degrees Dec. The local catalogue places it about 16,600 light-years away. Its referenced angular extent is approximately 19 by 19 arcminutes.
Observing tips
This is rated as a hard target at magnitude 6.3. It is associated with summer observing, with midnight placement typically strongest around July. From 52 degrees north its theoretical meridian altitude is about 7 degrees; local horizons and the live altitude chart determine the practical window.
A small telescope under reasonably dark skies is a good starting point; use the live altitude chart to choose its highest point.
What to expect
The SIMBAD classification for the matched source is GlC. A published radial velocity value is 174.8 km/s. The SIMBAD record currently connects it to 926 bibliographic references.
At roughly 19 arcminutes across, it benefits from a narrower field and adequate image scale. Use the listed 19 by 19 arcminute extent to check framing, and treat catalogue magnitude as integrated brightness rather than a direct measure of visual contrast.