NGC 6638 (GC)
Globular Cluster in Sagittarius
| R.A. | Dec. | Size | Mag | SB | Cnt.St | Type | Distance | Chart |
|---|---|---|---|---|---|---|---|---|
| 18h 30m 56.9s | -25° 29′ 45.9″ | 0′′ | 9.7 | -- | -- | GC | -- | -- |
Source: POSS-2 UK Schmidt Red (STScI) | Field: 10′ × 10′
Background
NGC 6638 is a small, faint globular cluster 30,000 light-years away in Sagittarius. The faintest of the three globulars surrounding λ Sgr (with M22 and M28).
My Observing Notes
25-cm (Meade 10-inch LX200, The Coffee Grinder): Sits 40' east of λ Sgr, completing the trio of globulars around that star (with M22 and M28). A more challenging target — appears as a faint diffuse glow at this aperture.(Friday, May 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)