- NGC 6231 (also known as Caldwell 76 or the Baby Scorpion Cluster) is an open cluster in the southern sky located half a degrees north of Zeta Scorpii. NGC 6231 is part of a swath of young, bluish stars in the constellation Scorpius known as the Scorpius OB1 association. The star Zeta1 (HR 6262) is a member of this association, while its brighter apparent partner, Zeta2 (HR 6271), is only 150 ly from Earth and so is not a member.
- New General Catalogue (Wikipedia)
The New General Catalogue of Nebulae and Clusters of Stars (abbreviated NGC) is an astronomical catalogue of deep-sky objects compiled by John Louis Emil Dreyer in 1888. The NGC contains 7,840 objects, including galaxies, star clusters and emission nebulae. Dreyer published two supplements to the NGC in 1895 and 1908, known as the Index Catalogues (abbreviated IC), describing a further 5,386 astronomical objects. Thousands of these objects are best known by their NGC or IC numbers, which remain in widespread use.