Trumpler 22 (Cl)

Open Cluster in Centaurus
R.A.Dec.SizeMag SBCnt.StTypeDistanceChart
14h 31m 04.7s-61° 10′ 03.0″10.0′7.912.6II2pCl----
Trumpler 22 DSS plate
Source: POSS-2 UK Schmidt Red (STScI) | Field: 15′ × 15′

Background

Trumpler 22 is a faint open cluster  5,500 light-years away in Centaurus, gravitationally bound to its brighter neighbour NGC 5617 just 0.5° to the north. The pair likely formed together in the same giant molecular cloud.

My Observing Notes

25-cm (Meade 10-inch LX200, The Coffee Grinder): Sits 0.5° south of NGC 5617 — a faint companion just resolvable at this aperture.(Friday, May 2025)

References

Charts

Trumpler 22 ultra-wide chart
Ultra-wide view (~25° field)
Trumpler 22 wide-field chart
Wide-field view with Telrad rings (4°, 2°, 0.5°)
Trumpler 22 finderscope view
Finderscope view (9×50 RACI, ~4.4° TFOV)
Trumpler 22 eyepiece view
Eyepiece view — 35 mm Panoptic on 12-inch f/5 (1.6° TFOV)