T Cephei — Variable Star in Cepheus
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1Physical Properties
Magnitude
7.33
Range
5.20 - 11.00
Period
389 days
Variable Type
Mira (Long-period Pulsating)
Spectral Type
M7IIIe
bright giant
Star Color
Red
(B-V 1.49)
Distance
1,631 ly
2Position & Identifiers
RA
21h 09m 32.0s
Dec
+68° 29' 25.0"
Constellation
Cepheus
(Cep)
HR
8113
HIP
104451
HD
202012
SAO
19229
Variable ID
T Cep
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.2 – 11.3 mag
Amplitude
6.1 mag
Period
388.9 d
Type
M
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Imp. | Imp. | Imp. |
| 50 mm finder 50mm finder | V. hard+ | V. hard | Imp. |
| 150 mm telescope 150mm scope | Medium+ | Medium | Hard+ |
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 T Cep (5.2–11.3)
Nearby stable stars for estimating brightness (AAVSO)
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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
M 5.2 - 11.3v. Period varies; mean period 388.14d, range 379 - 392.7d.
Weak-lined technetium star. SiO source. Also classified M5.5e-M8.8e.
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.
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Article
Cepheus
Mythology, bright stars, and deep-sky highlights.
Constellation
