NGC 5138 (OC)
Open Cluster in Centaurus
| R.A. | Dec. | Size | Mag | SB | Cnt.St | Type | Distance | Chart |
|---|---|---|---|---|---|---|---|---|
| 13h 27m 18.5s | -59° 02′ 06.5″ | 7.0′ | 7.6 | 11.6 | II2p | OC | -- | -- |
Source: POSS-2 UK Schmidt Red (STScI) | Field: 15′ × 15′
Background
NGC 5138 is a sparse open cluster 7,500 light-years away in Centaurus. Around 130 million years old, it is one of the older inner-Galactic-disc open clusters in this region.
My Observing Notes
25-cm (Meade 10-inch LX200, The Coffee Grinder): A large, sparsely populated cluster of 40 stars with no structured core. Would have benefited from a wider field of view than the 26 mm eyepiece.(Thursday, April 2025)
References
Charts
Ultra-wide view (~25° field)
Wide-field view with Telrad rings (4°, 2°, 0.5°)
Finderscope view (9×50 RACI, ~4.4° TFOV)
Eyepiece view — 35 mm Panoptic on 12-inch f/5 (1.6° TFOV)