Globular Cluster · Ophiucus

M9 NGC 6333

Magnitude
7.7
Season
Summer
Difficulty
Moderate
Star-hop chart
M90.0° field0° rotation
Stars

Drag to pan · scroll or pinch to zoom

Imaging reference
NGC 6333 (M9) Globular Cluster

Observer's guide

About NGC 6333

NGC 6333 (M9) is catalogued as a globular cluster in Ophiucus. Its J2000 position is RA 17:19:11.78, Dec -18:30:58.5, corresponding to 259.7991 degrees RA and -18.5162 degrees Dec. The local catalogue places it about 26,700 light-years away. Its referenced angular extent is approximately 8.7 by 8.7 arcminutes.

Observing tips

StarWatchr rates this as a moderate target at magnitude 7.7. It is associated with summer observing, with midnight placement typically strongest around June. From 52 degrees north its theoretical meridian altitude is about 19.5 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 310.8 km/s. The SIMBAD record currently connects it to 350 bibliographic references.

At roughly 8.7 arcminutes across, it benefits from a narrower field and adequate image scale. Use the listed 8.7 by 8.7 arcminute extent to check framing, and treat catalogue magnitude as integrated brightness rather than a direct measure of visual contrast.

Sourced catalogue data

Scientific record

Measurements for M9 are kept separate from practical observing guidance.

Coordinates (J2000/ICRS)
RA 259.799083° · Dec -18.51625°
SIMBAD classification
GlC
Angular extent
8.7′ × 8.7′
Position angle
Radial velocity
310.75 km/s
Redshift
0.00103709
Linked bibliography
350 references
Best midnight placement
June
Observable latitude range
-90° to 71.5°

Source: SIMBAD astronomical database (CDS, Strasbourg) (ODbL; checked 2026-08-09). Catalogue values may change when new measurements are published.

Your selected location

24-hour altitude profile

Use the highest part of the curve to plan the clearest observing window.

90°
60°
30°
-10°
10:25
14:25
18:25
22:25
02:25
06:25
10:25
Live sky imagery