NGC 6558 — Globular Cluster in Sagittarius
Fair (29/100)
Observe
1Properties
Magnitude
11.29
Angular Size
5.4′
glob. cl. , pB, pL, R, glbM, rrr, st 16
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Position & Identifiers
2How easy to spot?
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| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | Hard+ | Hard | V. hard+ |
| 150 mm Newton 150mm Newt. | Medium+ | Medium | Hard+ |
| Celestron C8 (203 mm SCT) C8 203mm | Medium+ | Medium+ | Medium |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
Easy
on Seestar S50
3Visibility
Set a location in User Settings to see visibility data.
Best season
May – Jul
(peak: Jun)
4
Eyepiece View
125x
TFOV: 0.4°
Lim. mag: 13.6
NGC 6558 · 5.4′ diameter · N up, E left
5
Best Magnification
Explore
6
Classification Decoder
Nearby in the Sky
Other targets within a few degrees — pan your scope a little and keep exploring.
Visibility scores assume a 150 mm Newton at Bortle 4.
NGC 6569
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 8.7
0.7°
Sagittarius
NGC 6528
Compact globular cluster
Globular Cluster
mag 9.5
2.1°
Sagittarius
NGC 6522
Compact globular cluster
Globular Cluster
mag 8.6
2.3°
Sagittarius
Gamma Sgr
HIP 88567; Gamma1 Sagittarii
Pulsating variable, period 7.6d
Variable Star
mag 4.69
2.5°
Sagittarius
NGC 6624
Compact globular cluster
Globular Cluster
mag 8.3
3.2°
Sagittarius
NGC 6520
Open cluster
Open Cluster
mag 8.0
4.2°
Sagittarius
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