Theta Delphini — Star in Delphinus
Observe
1Physical Properties
Magnitude
5.72
Spectral Type
K3Ib
supergiant
Star Color
Red
(B-V 1.53)
2Position & Identifiers
RA
20h 38m 43.9s
Dec
+13° 18' 54.0"
Constellation
Delphinus
(Del)
HR
7892
HIP
101882
HD
196725
SAO
106342
Bayer
Theta
Flamsteed
8 Del
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard+ | Hard | V. hard+ |
| 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
6
Size Comparison
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7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
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10
Stellar Lifecycle
11
Blackbody Spectrum
12
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
13
Stellar Fusion
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
Delphinus
Mythology, bright stars, and deep-sky highlights.
Constellation
