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NGC 2331 — Open Cluster in Gemini

Open Cluster Good (56/100)
Magnitude 9.0m OpenCluster Gemini (Gem) Visible
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1Properties

Magnitude 9.0
Angular Size 4.8′
Cl, L, vlC, S Cl inv

Position & Identifiers

RA 07h 06m 59.8s
Dec +27° 15' 41.8"
Constellation Gemini (Gem)
Catalog NGC 2331

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 Dec – Feb (peak: Jan)

4 Eyepiece View

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125x TFOV: 0.4° Lim. mag: 13.6
N E

NGC 2331 · 4.8′ diameter

5 Best Magnification

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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 2266
Easy
Open cluster
Open Cluster mag 10.0 5.3° Gemini
Mekbuda
Zeta Gem
Medium
Pulsating variable, period 10.1d
Variable Star mag 3.79 6.7° Gemini
NGC 2274
Hard+
Elliptical galaxy
Galaxy mag 13.0 7.6° Gemini
NGC 2420
Easy
Open cluster
Open Cluster mag 8.3 9.1° Gemini
NGC 2304
Easy
Open cluster
Open Cluster mag 10.0 9.7° Gemini
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