TU Geminorum — Variable Star in Gemini
Excellent (60/100)
Observe
1Physical Properties
Magnitude
7.30
Range
6.88 - 8.0
Period
217 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
C
Star Color
Deep ruby red
(B-V 3.00)
2Position & Identifiers
3How easy to follow?
Magnitude
6.9 – 8.0 mag
Amplitude
1.1 mag
Period
217 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Imp. | Imp. | Imp. |
| 50 mm finder 50mm finder | Medium+ | Medium+ | Medium |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
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 TU Gem (6.9–8.0)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
8
Compare Stars
9
Spectral Classification
10
Hertzsprung-Russell Diagram
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11
Stellar Lifecycle
12
Blackbody Spectrum
13
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
14
Stellar Fusion
Discover
15Stellar Notes
Carbon star; Period 230d
Carbon star
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.
M35
Shoe-Buckle Cluster
Open cluster
Open Cluster
mag 5.3
1.7°
Gemini
3 Gem
Variable star, range 7.0–10.0
Variable Star
mag 5.75
2.9°
Gemini
6 Gem
Mira-type variable, range 5.7–8.1
Variable Star
mag 6.39
3.1°
Gemini
TV Gem
Variable star, range 6.3–7.5
Variable Star
mag 6.56
4.2°
Gemini
48 Aur
Pulsating variable, period 3.7d
Variable Star
mag 5.55
5.9°
Auriga
M1
Crab Nebula
Supernova remnant
Supernova Remnant
mag 8.4
9.2°
Taurus
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