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NGC 2304 — Open Cluster in Gemini

Open Cluster Good (43/100)
Magnitude 10.0m OpenCluster Gemini (Gem) Visible
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1Properties

Magnitude 10.0
Angular Size 4.8′
Cl, pL, Ri, mC, st vS

Position & Identifiers

RA 06h 55m 11.6s
Dec +17° 59' 34.1"
Constellation Gemini (Gem)
Catalog NGC 2304

2How easy to spot?

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Telescope Bortle 3 Bortle 4 Bortle 5
80mm refr. Medium+ Medium 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 Nov – Jan (peak: Dec)

4 Eyepiece View

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125x TFOV: 0.4° Lim. mag: 13.6
N E

NGC 2304 · 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.

Mekbuda
Zeta Gem
Medium
Pulsating variable, period 10.1d
Variable Star mag 3.79 3.3° Gemini
NGC 2355
Easy
Open cluster
Open Cluster mag 10.0 6.7° Gemini
NGC 2259
Medium+
Open cluster
Open Cluster mag 11.0 8.2° Monoceros
Eskimo Nebula
NGC 2392
Medium+
Small bright planetary nebula
Planetary Nebula mag 9.2 8.5° Gemini
NGC 2395
Easy
Open cluster
Open Cluster mag 8.0 8.9° Gemini
NGC 2266
Easy
Open cluster
Open Cluster mag 10.0 9.4° Gemini
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