Observer's guide
About NGC 6613
NGC 6613 (M18) is catalogued as an open cluster in Sagittarius. Its J2000 position is RA 18:19:58.49, Dec -17:06:07.1, corresponding to 274.9875 degrees RA and -17.0883 degrees Dec. The local catalogue places it about 4,900 light-years away. Its referenced angular extent is approximately 5 by 5 arcminutes.
Observing tips
This is rated as a moderate target at magnitude 7.5. It is associated with summer observing, with midnight placement typically strongest around June. From 52 degrees north its theoretical meridian altitude is about 20.9 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 OpC. A published radial velocity value is -14 km/s. The SIMBAD record currently connects it to 93 bibliographic references.
At roughly 5 arcminutes across, it benefits from a narrower field and adequate image scale. Use the listed 5 by 5 arcminute extent to check framing, and treat catalogue magnitude as integrated brightness rather than a direct measure of visual contrast.