C76
NGC 6231
Properties
Position & Identifiers
Visibility
Set a location in User Settings to see visibility data.
Survey Image
Loading survey image…
About C76
Description
NGC 6231 is a bright, compact open cluster in Scorpius, about 5,900 light-years away. At magnitude 2.6 it is visible to the naked eye, and it forms the core of the much larger Scorpius OB1 association. The cluster contains numerous hot O- and B-type stars.
Observing Tips
Stunning in binoculars and small telescopes. Located just north of the Scorpion's tail near Zeta Scorpii. A telescope at 40-80x reveals dozens of bright blue-white stars. Best in summer evenings from locations with a good southern horizon.
History
Known since antiquity as a bright patch near the Scorpion's stinger. Giovanni Battista Hodierna first resolved it as a cluster before 1654. Sometimes called the Northern Jewel Box for its brightness and rich star field.
Fun Facts
NGC 6231 is only about 3.2 million years old, one of the youngest clusters visible to the naked eye. Its O-type stars will burn through their fuel and explode as supernovae within the next few million years.
Community Photos (1)
Credit: Lithopsian. License: CC BY 4.0. (Wikimedia Commons)
Skybred Mar 2, 2026