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NGC 2129 — Open Cluster in Gemini

Open Cluster Good (54/100)
Magnitude 6.7m OpenCluster Gemini (Gem) Visible
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1Properties

Magnitude 6.7
Angular Size 3.9′
Cl, pL, 40 or 50 st 8...15

Position & Identifiers

RA 06h 01m 06.5s
Dec +23° 19' 19.9"
Constellation Gemini (Gem)
Catalog NGC 2129

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

NGC 2129 · 3.9′ 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.

IC 2157
Easy
Open cluster
Open Cluster mag 8.4 1.1° Gemini
NGC 2158
Easy
Open cluster
Open Cluster mag 8.6 1.6° Gemini
3 Gem
Easy
Variable star, range 7.0–10.0
Variable Star mag 5.75 2.0° Gemini
M35
NGC 2168
Easy
Open cluster
Open Cluster mag 5.1 2.1° Gemini
NGC 2175
Easy
Rich open cluster
Open Cluster mag 6.8 3.6° Orion
M1
Crab Nebula
Medium+
Supernova remnant
Supernova Remnant mag 8.4 6.3° Taurus
Show on Map

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