| Object Type | Open Cluster |
| Constellation | Puppis |
| Magnitude | 9.3 |
| Size | 12.0' x 12.0' |

Number 111 in the Herschel 400 list is NGC 2509. This is a fairly large cluster in Puppis. Most of the stars are rather faint, with the 3 brightest forming a large, almost equilateral triangle surrounding the cluster. The faint, edge-on spiral galaxy visible on the lower right of the cluster is PGC 79360.