Nu Geminorum — Star in Gemini
Observe
1Physical Properties
Magnitude
4.15
Spectral Type
B6IIIe
bright giant
Star Color
Blue-white
(B-V -0.13)
Distance
362 ly
2Position & Identifiers
RA
06h 28m 57.8s
Dec
+20° 12' 44.0"
Constellation
Gemini
(Gem)
HR
2343
HIP
30883
HD
45542
SAO
78423
Bayer
Nu
Flamsteed
18 Gem
Double Cat
5103
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | Medium+ | Medium |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
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Best season
Nov – Jan
(peak: Dec)
5Survey Image
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7
Size Comparison
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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
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15Stellar Notes
AA' probably combined light and color. This may be the SB pair, 4.3, 6.0v, sep. 0.2". B, 8.5V A1V at 113", | vsini 141k/s, is binary with C, 8.9v, sep. 0.2". Component P, 15.1V at 24" optical. Other components faint at 54" | to 92".
ADS 5103A, 9.6y. Resolved by speckle interferometry 1983.93, sep. 0.07".
Hyades group.
Shell star.
16
Light Travel Time Machine
17
Relativistic Travel
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.
Tejat Posterior
HIP 30343; Mu Geminorum; 13 Geminorum
Cool red giant
Double Star
mag 2.88
2.7°
Gemini
Collinder 89
Open cluster
Open Cluster
mag 5.7
4.3°
Gemini
TV Gem
Variable star, range 6.3–7.5
Variable Star
mag 6.56
4.3°
Gemini
NGC 2247
Reflection nebula around a bright star
Reflection Nebula
mag 8.50
9.9°
Monoceros
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