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IC 2157 — Open Cluster in Gemini

Open Cluster Good (42/100)
Magnitude 8.4m OpenCluster Gemini (Gem) Visible
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1Properties

Magnitude 8.4
Angular Size 2.7′
Cl, S

Position & Identifiers

RA 06h 04m 47.6s
Dec +24° 04' 15.6"
Constellation Gemini (Gem)
Catalog IC 2157

2How easy to spot?

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

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

Medium 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

IC 2157 · 2.7′ 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 2158
Easy
Open cluster
Open Cluster mag 8.6 0.6° Gemini
M35
NGC 2168
Easy
Open cluster
Open Cluster mag 5.1 1.0° Gemini
NGC 2129
Easy
Rich open cluster
Open Cluster mag 6.7 1.1° Gemini
3 Gem
Easy
Variable star, range 7.0–10.0
Variable Star mag 5.75 1.5° Gemini
Collinder 89
Easy
Open cluster
Open Cluster mag 5.7 3.1° Gemini
M1
Crab Nebula
Medium+
Supernova remnant
Supernova Remnant mag 8.4 7.3° Taurus
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