X Cygni — Variable Star in Cygnus
Excellent (70/100)
Observe
1Physical Properties
Magnitude
6.47
Range
5.85 - 6.91
Period
16.4 days
Variable Type
Classical Cepheid
Spectral Type
F7Ib-G8Ib
supergiant
Star Color
Red
(B-V 1.23)
2Position & Identifiers
RA
20h 43m 24.2s
Dec
+35° 35' 16.0"
Constellation
Cygnus
(Cyg)
HR
7932
HIP
102276
HD
197572
SAO
70423
Variable ID
X Cyg
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.9 – 6.9 mag
Amplitude
1.1 mag
Period
16.39 d
Type
DCEP
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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 | 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
Jun – Aug
(peak: Jul)
5Survey Image
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6Light Curve
7Comparison Stars for X Cyg (5.8–6.9)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
8
Size Comparison
Querying VizieR for stellar data…
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
CDelta 5.85 - 6.91, 16.386332d. Period changes.
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.
East Veil Nebula
NGC 6992
Supernova remnant
Supernova Remnant
mag 7.0
4.7°
Cygnus
M29
NGC 6913
Rich open cluster
Open Cluster
mag 6.6
4.9°
Cygnus
DT Cyg
Pulsating variable, period 2.5d
Variable Star
mag 5.82
6.5°
Cygnus
RS Cyg
Mira-type variable, range 6.5–9.5
Variable Star
mag 6.50
6.7°
Cygnus
T Vul
Pulsating variable, period 4.4d
Variable Star
mag 5.77
7.5°
Vulpecula
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