Theta Cephei — Star in Cepheus
Observe
1Physical Properties
Magnitude
4.22
Spectral Type
A7III
giant
Star Color
Yellow-white
(B-V 0.20)
Distance
86 ly
2Position & Identifiers
RA
20h 29m 34.9s
Dec
+62° 59' 39.0"
Constellation
Cepheus
(Cep)
HR
7850
HIP
101093
HD
195725
SAO
18897
Bayer
Theta
Flamsteed
2 Cep
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | Medium+ | Medium |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 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
Jun – Aug
(peak: Jul)
5Survey Image
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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
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15Stellar Notes
840.6d, K 13.9k/s, V0 -6.4k/s, asini 161. Unresolved by speckle interferometry.
Also classified Am.
16
Light Travel Time Machine
17
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.
NGC 6939
Open cluster
Open Cluster
mag 7.8
2.3°
Cepheus
Fireworks Galaxy
NGC 6946
Bright spiral galaxy
Galaxy
mag 8.9
2.9°
Cepheus
Alderamin
HIP 105199; Alpha Cephei; 5 Cephei
Bright naked-eye star, mag 2.4
Star
mag 2.44
5.6°
Cepheus
Iris Nebula
NGC 7023
Reflection nebula around a bright star
Reflection Nebula
mag 6.8
6.2°
Cepheus
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