IC 4291 — Open Cluster in Centaurus
Fair (25/100)
Observe
1Properties
Magnitude
9.70
Angular Size
5.1′
pS, R, bM
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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
Easy
on Seestar S50
3Visibility
Set a location in User Settings to see visibility data.
Best season
Mar – May
(peak: Apr)
4
Eyepiece View
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 5168
Open cluster
Open Cluster
mag 9.1
1.3°
Centaurus
NGC 5281
Rich open cluster
Open Cluster
mag 5.9
1.4°
Centaurus
NGC 5316
Rich open cluster
Open Cluster
mag 6.0
2.0°
Centaurus
NGC 5288
Open cluster
Open Cluster
mag 12.0
2.9°
Circinus
NGC 5189
Planetary nebula — try an OIII filter
Planetary Nebula
mag 10.0
3.9°
Musca
R Cen
Mira-type variable, range 5.3–11.8
Variable Star
mag 6.39
5.3°
Centaurus
Coalsack Nebula
Dark nebula — shows as a void against the Milky Way
Dark Nebula
mag 12.0
5.7°
Crux
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