V1339 Cygni — Variable Star in Cygnus
Excellent (67/100)
Observe
1Physical Properties
Magnitude
6.17
Range
5.90 - 6.45
Period
35 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
M4III:
giant
Star Color
Red
(B-V 1.55)
Distance
1,087 ly
2Position & Identifiers
RA
21h 42m 08.4s
Dec
+45° 45' 57.0"
Constellation
Cygnus
(Cyg)
HR
8298
HIP
107140
HD
206632
SAO
51204
Variable ID
V1339 Cyg
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3How easy to follow?
Magnitude
5.9 – 7.1 mag
Amplitude
1.2 mag
Period
35 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard | V. hard | Imp. |
| 50 mm finder 50mm finder | Easy | 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
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Best season
Jul – Sep
(peak: Aug)
5Survey Image
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6Light Curve
7Comparison Stars for V1339 Cyg (5.9–7.1)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
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
Discover
16Stellar Notes
SRb 5.9 - 7.1v, 35?d.
17
Light Travel Time Machine
18
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.
W Cyg
Semi-regular variable, range 5.1–6.8
Variable Star
mag 5.53
1.1°
Cygnus
IC 5146 C
Open cluster
Open Cluster
mag 7.2
2.5°
Cygnus
Cocoon Nebula
IC 5146
Emission nebula — try an OIII filter
Emission Nebula
mag 10.0
2.5°
Cygnus
AR Lac
Eclipsing binary, period 2.0d
Variable Star
mag 6.11
4.6°
Lacerta
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