RS Cygni — Variable Star in Cygnus
Excellent (66/100)
Observe
1Physical Properties
Magnitude
6.50
Range
6.5 - 9.5
Period
417 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
C
Star Color
Deep ruby red
(B-V 3.00)
2Position & Identifiers
RA
20h 13m 24.0s
Dec
+38° 43' 45.0"
Constellation
Cygnus
(Cyg)
HR
9115
HIP
99653
HD
192443
Variable ID
RS Cyg
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3How easy to follow?
Magnitude
6.5 – 9.5 mag
Amplitude
3.0 mag
Period
417 d
Type
SRA
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Imp. | Imp. | Imp. |
| 50 mm finder 50mm finder | Medium | Hard+ | Hard |
| 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
Jun – Aug
(peak: Jul)
5Light Curve
6Comparison Stars for RS Cyg (6.5–9.5)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
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
Discover
15Stellar Notes
Carbon star; Period 417d
Carbon star
Survey Image
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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.
Crescent Nebula
NGC 6888
Emission nebula — try an OIII filter
Emission Nebula
mag 10.0
0.5°
Cygnus
IC 4996
Open cluster
Open Cluster
mag 7.3
1.3°
Cygnus
V973 Cyg
Semi-regular variable, range 6.1–6.8
Variable Star
mag 6.34
5.8°
Cygnus
X Cyg
Pulsating variable, period 16.4d
Variable Star
mag 6.47
6.7°
Cygnus
RR Lyr
Pulsating variable, period 13.6h
Variable Star
mag 7.10
9.9°
Lyra
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