Open Cluster · Scorpius

C76 NGC 6231

Magnitude
2.6
Season
Summer
Difficulty
Very Easy
Star-hop chart
C760.0° field0° rotation
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Imaging reference
NGC 6231 (C76) Open Cluster

Observer's guide

About NGC 6231

NGC 6231 (C76) is catalogued as an open cluster in Scorpius. Its J2000 position is RA 16:54:10, Dec -41:48:43, corresponding to 253.545 degrees RA and -41.8119 degrees Dec. The local catalogue places it about 6,000 light-years away. Its referenced angular extent is approximately 120 by 120 arcminutes.

Observing tips

StarWatchr rates this as a very easy target at magnitude 2.6. It is associated with summer observing, with midnight placement typically strongest around May. From 52 degrees north its theoretical meridian altitude is about 0 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 OpC. A published radial velocity value is -28.2 km/s. The SIMBAD record currently connects it to 568 bibliographic references.

At roughly 120 arcminutes across, it favors a wide-field imaging setup. Use the listed 120 by 120 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 C76 are kept separate from practical observing guidance.

Coordinates (J2000/ICRS)
RA 253.5450° · Dec -41.811944°
SIMBAD classification
OpC
Angular extent
120′ × 120′
Position angle
Radial velocity
-28.19 km/s
Redshift
-0.00009401
Linked bibliography
568 references
Best midnight placement
May
Observable latitude range
-90° to 48.2°

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

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24-hour altitude profile

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