NGC 6638 — Globular Cluster in Sagittarius
Good (44/100)
Observe
1Properties
Magnitude
9.2
Angular Size
4.2′
glob. cl. , B, S, R, rr
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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. | Easy | Medium+ | Medium+ |
| 150 mm Newton 150mm Newt. | Easy | Easy | Easy |
| Celestron C8 (203 mm SCT) C8 203mm | Easy | Easy | Easy |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
Medium
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 6638 · 4.2′ 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.
M28
NGC 6626
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 6.8
1.6°
Sagittarius
M22
Great Sagittarius Cluster
Large bright globular cluster
Globular Cluster
mag 5.1
2.0°
Sagittarius
NGC 6642
Compact globular cluster
Globular Cluster
mag 8.8
2.0°
Sagittarius
NGC 6583
Open cluster
Open Cluster
mag 10.0
4.8°
Sagittarius
NGC 6553
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 8.3
4.9°
Sagittarius
IC 4678
Diffuse nebula
Diffuse Nebula
mag 10.40
5.5°
Sagittarius
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