SU Cygni — Variable Star in Cygnus
Excellent (62/100)
Observe
1Physical Properties
Magnitude
6.82
Range
6.44 - 7.22
Period
3.8 days
Variable Type
Classical Cepheid
Spectral Type
F2I
supergiant
Star Color
Yellow
(B-V 0.64)
2Position & Identifiers
RA
19h 44m 48.7s
Dec
+29° 15' 53.0"
Constellation
Cygnus
(Cyg)
HR
7518
HIP
97150
HD
186688
SAO
87659
Variable ID
SU Cyg
Querying VizieR catalog...
3How easy to follow?
Magnitude
6.4 – 7.2 mag
Amplitude
0.8 mag
Period
3.85 d
Type
DCEP
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard | Imp. | Imp. |
| 50 mm finder 50mm finder | Medium | Medium | Medium |
| 150 mm telescope 150mm scope | Medium+ | Medium+ | 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
Jun – Aug
(peak: Jul)
5Survey Image
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6Light Curve
7Comparison Stars for SU Cyg (6.4–7.2)
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
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16Stellar Notes
CDelta 6.44 - 7.22V, 3.8455473d. Period changes.
Also classified F0-G1II, G0III and F2-G0II-III + B7V.
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.
NGC 6834
Open cluster
Open Cluster
mag 7.8
1.6°
Cygnus
Albireo
HIP 95951; Beta2 Cygni; 6 Cygni
Colorful double, sep 34.7″
Double Star
mag 5.11
3.3°
Cygnus
M56
NGC 6779
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 8.3
6.2°
Lyra
V473 Lyr
Pulsating variable, period 1.5d
Variable Star
mag 6.16
6.5°
Lyra
22 Vul
Observable variable star
Variable Star
mag 5.15
9.0°
Vulpecula
U Vul
Pulsating variable, period 8.0d
Variable Star
mag 7.14
9.1°
Vulpecula
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