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Constellations / Gemini

Gemini

Geminorum

Northern 514 sq° Gem

Brightest star: Pollux

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Mythology

The Twins Castor and Pollux, inseparable brothers from Greek mythology. Pollux was immortal (son of Zeus) while Castor was mortal. Zeus placed them both in the sky together.

Observing Highlights

Castor is a remarkable sextuple star system. Contains the open cluster M35, the Eskimo Nebula (NGC 2392), and the Jellyfish Nebula. A zodiacal winter constellation and radiant of the Geminid meteors.

Main Stars

20
Pollux

Pollux

HIP 37826; Beta Gem; 78 Gem

1.14 mag 39.8″ B: 13.7 G9III
Alhena

Alhena

HIP 31681; Gamma Gem; 24 Gem

1.93 mag 140.5″ B: 13.0 A1.5IV
Castor

Castor

HIP 36850; Alpha Gem; 66 Gem

1.98 mag 5.4″ B: 3.0 A1.5IV+
Tejat Posterior

Tejat Posterior

HIP 30343; Mu Gem; 13 Gem

2.88 mag 2.75 - 3.02 SR M3IIIab
Mebsuta

Mebsuta

HIP 32246; Epsilon Gem; 27 Gem

2.98 mag 109.9″ B: 9.6 G9Ib
Propus

Propus

HIP 29655; Eta Gem; 7 Gem

3.28 mag 1.9″ B: 6.2 M2IIIa
Alzirr

Alzirr

HIP 32362; Xi Gem; 31 Gem

3.36 mag F5IV-V
Wasat

Wasat

HIP 35550; Delta Gem; 55 Gem

3.53 mag 5.5″ B: 8.2 F2V Fe-0.5
Kappa Gem

HIP 37740; Kappa Gem; 77 Gem

3.57 mag 7.0″ B: 10.0 G9III
Lambda Gem

HIP 35350; Lambda Gem; 54 Gem

3.58 mag 9.7″ B: 10.7 A3V
Theta Gem

HIP 33018; Theta Gem; 34 Gem

3.60 mag 3.2 - 3.9 A2IV
Mekbuda

Mekbuda

HIP 34088; Zeta Gem; 43 Gem

3.79 mag 3.62 - 4.18 DCEP G1Ib
Iota Gem

HIP 36046; Iota Gem; 60 Gem

3.79 mag 0.1″ B: 4.7 G9IIIb
Upsilon Gem

HIP 36962; Upsilon Gem; 69 Gem

4.06 mag 55.2″ B: 13.2 M0III-IIIb
Nu Gem

HIP 30883; Nu Gem; 18 Gem

4.15 mag 112.8″ B: 8.0 B6IIIe
1 Gem

HIP 28734; 1 Gem

4.16 mag 0.1″ B: 5.5 G7III
Rho Gem

HIP 36366; Rho Gem; 62 Gem

4.18 mag 1.2″ B: 12.5 F0V
Sigma Gem

HIP 37629; Sigma Gem; 75 Gem

4.28 mag 195.5″ B: 10.8 K1III
Tau Gem

HIP 34693; Tau Gem; 46 Gem

4.41 mag 1.8″ B: 11.0 K2-III
30 Gem

HIP 32249; 30 Gem

4.49 mag 21.2″ B: 13.0 K0IIICN1Ca1

Double Stars

15
Castor

Castor

HIP 36850; Alpha Gem; 66 Gem

1.98 mag 5.4″ B: 3.0 A1.5IV+
Wasat

Wasat

HIP 35550; Delta Gem; 55 Gem

3.53 mag 5.5″ B: 8.2 F2V Fe-0.5
38 Gem

HIP 33202; 38 Gem

4.65 mag 7.3″ B: 7.8 F0Vp
HIP 36690
6.54 mag 11.7″ B: 8.2 K0II-III+F8V
56 Gem

HIP 35699; 56 Gem

5.10 mag 13.5″ B: 12.2 M0IIIab
Pi Gem

HIP 38016; Pi Gem; 80 Gem

5.14 mag 19.0″ B: 11.4 M1IIIa
Pollux

Pollux

HIP 37826; Beta Gem; 78 Gem

1.14 mag 39.8″ B: 13.7 G9III
HIP 36616
5.42 mag 5.6″ B: 10.1 gK2
Kappa Gem

HIP 37740; Kappa Gem; 77 Gem

3.57 mag 7.0″ B: 10.0 G9III
HIP 34358
5.91 mag 10.1″ B: 12.4 gK4
Upsilon Gem

HIP 36962; Upsilon Gem; 69 Gem

4.06 mag 55.2″ B: 13.2 M0III-IIIb
30 Gem

HIP 32249; 30 Gem

4.49 mag 21.2″ B: 13.0 K0IIICN1Ca1
45 Gem

HIP 34440; 45 Gem

5.44 mag 15.9″ B: 10.9 G8III
52 Gem

HIP 35025; 52 Gem

5.82 mag 30.5″ B: 12.7 M1III
65 Gem

HIP 36429; 65 Gem

5.01 mag 10.7″ B: 13.6 K2III

Variable Stars

9
Mekbuda

Mekbuda

HIP 34088; Zeta Gem; 43 Gem

3.79 mag 3.62 - 4.18 DCEP G1Ib
Tejat Posterior

Tejat Posterior

HIP 30343; Mu Gem; 13 Gem

2.88 mag 2.75 - 3.02 SR M3IIIab
6 Gem

HIP 29450; 6 Gem

6.39 mag 5.74 - 7.4 SRC M1-2Ia-Iab
IS Gem

HIP 32740

5.71 mag K3II
R Gem

HIP 34356

7.68 mag S3.9e
TV Gem

HIP 29416

6.56 mag M0-1Iab
51 Gem

HIP 34909; 51 Gem

5.00 mag M4IIIab
Theta Gem

HIP 33018; Theta Gem; 34 Gem

3.60 mag 3.2 - 3.9 A2IV
TU Gem

HR 9120

7.30 mag 6.88 - 8.0 SRB C

Deep Sky Objects

30
Open Cluster (10)
M35

NGC 2168

5.3 mag 28.
NGC 2129
6.7 mag 7.
NGC 2331
9.0 mag 18.
NGC 2395
8.0 mag 12.
NGC 2420
8.3 mag 10.
NGC 2158
8.6 mag 5.
NGC 2304
10.0 mag 5.
IC 2157
8.4 mag 7.
NGC 2266
10.0 mag 7.
NGC 2355
10.0 mag 9.
Galaxy (17)
NGC 2339
11.6 mag 2.8 Sbc
NGC 2357
14.0 mag 4.5 Sc
NGC 2341
14.0 mag 1.1 Sc
NGC 2342
13.0 mag 1.6 Sc
NGC 2389
12.8 mag 2.1 SABc
NGC 2290
15.0 mag 1.5 Sa
NGC 2487
14.0 mag 2.8 Sb
IC 2185
15.0 mag 0.5 Sbc
IC 2211
14.0 mag 0.8 SBa
IC 2181
15.0 mag 1.0 Sab
IC 2203
14.0 mag 1.2 SBc
IC 2204
15.0 mag 1.1 Sab
NGC 2379
13.5 mag 1.1 S0
IC 2180
15.0 mag 1.2 Sab
IC 2201
15.0 mag 1.3 Sa
IC 2207
15.0 mag 2.0 SBc
NGC 2275
14.0 mag Sa
Planetary Nebula (2)
Eskimo Nebula

NGC 2392

C39

9.2 mag 0.8
NGC 2371
13.0 mag 0.9
Supernova Remnant (1)
IC 443
— mag 50.