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Collinder 261 — Open Cluster in Musca

Open Cluster Good (41/100)
Magnitude 9.0m OpenCluster Musca Visible
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1Properties

Magnitude 9.0
Angular Size 9 arcmin
Open Cluster

Position & Identifiers

RA 12h 37m 57.0s
Dec -68° 22' 00.0"
Constellation Musca
Catalog Cr 261

2How easy to spot?

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Telescope Bortle 3 Bortle 4 Bortle 5
80mm refr. Easy Easy Medium+
150mm Newt. Easy Easy Easy
C8 203mm Easy Easy Easy
Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

Easy on Seestar S50

3Visibility

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Best season Feb – Apr (peak: Mar)

4 Eyepiece View

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125x TFOV: 0.4° Lim. mag: 13.6
N E

Collinder 261 · 9.0′ diameter

5 Best Magnification

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.

R Mus
Medium
Pulsating variable, period 7.5d
Variable Star mag 6.33 1.1° Musca
NGC 4833
Easy
Globular cluster — dense ball of ancient stars
Globular Cluster mag 7.4 3.1° Musca
NGC 4463
Easy
Open cluster
Open Cluster mag 7.2 3.7° Musca
NGC 4815
Easy
Open cluster
Open Cluster mag 8.6 3.9° Musca
C98
NGC 4609
Easy
Rich open cluster
Open Cluster mag 6.9 5.4° Crux
NGC 4052
Easy
Open cluster
Open Cluster mag 9.0 6.3° Crux
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