3 Geminorum — Variable Star in Gemini
Showpiece (78/100)
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1Physical Properties
Magnitude
5.75
Range
5.71 - 5.77
Period
6.8 days
Variable Type
ACYG
Spectral Type
B2.5Ib
supergiant
Star Color
Yellow-white
(B-V 0.21)
2Position & Identifiers
RA
06h 09m 44.0s
Dec
+23° 06' 48.0"
Constellation
Gemini
(Gem)
HR
2173
HIP
29225
HD
42087
SAO
78050
Flamsteed
3 Gem
Double Cat
4751
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3How easy to follow?
Magnitude
7.0 – 10.0 mag
Amplitude
3.0 mag
Period
6.81 d
Type
ACYG
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Imp. | Imp. | Imp. |
| 50 mm finder 50mm finder | Hard+ | Hard | V. hard+ |
| 150 mm telescope 150mm scope | Easy | Easy | Medium+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
Best season
Nov – Jan
(peak: Dec)
5Survey Image
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6Light Curve
7Comparison Stars for 3 Gem (7.0–10.0)
Nearby stable stars for estimating brightness (AAVSO)
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8
Size Comparison
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9
Compare Stars
10
Spectral Classification
11
Hertzsprung-Russell Diagram
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12
Stellar Lifecycle
13
Blackbody Spectrum
14
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
15
Stellar Fusion
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16Stellar Notes
ADS 4751B, 7.0 - 10.0v.
AB binary, combined mag., colors. C 14.4v at 18".
Gem OB1.
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.
6 Gem
Mira-type variable, range 5.7–8.1
Variable Star
mag 6.39
0.6°
Gemini
NGC 2158
Open cluster
Open Cluster
mag 8.6
1.1°
Gemini
TV Gem
Variable star, range 6.3–7.5
Variable Star
mag 6.56
1.3°
Gemini
TU Gem
Semi-regular variable, range 6.9–8.0
Variable Star
mag 7.30
2.9°
Gemini
Y Tau
Semi-regular variable, range 6.4–7.3
Variable Star
mag 6.95
6.1°
Taurus
M1
Crab Nebula
Supernova remnant
Supernova Remnant
mag 8.4
8.2°
Taurus
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