Observe
1Physical Properties
Magnitude
5.48
Spectral Type
gG6
Star Color
Orange
(B-V 0.93)
2Position & Identifiers
RA
20h 58m 25.9s
Dec
+10° 50' 21.0"
Constellation
Delphinus
(Del)
HR
8030
HIP
103527
HD
199665
SAO
106712
Flamsteed
18 Del
Querying VizieR catalog...
3How easy to spot?
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and configure your equipment and default location to see a personalized row.
| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium | Hard+ | 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
Set a location in User Settings to see visibility data.
Best season
Jun – Aug
(peak: Jul)
5Survey Image
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Explore
6
Size Comparison
Querying VizieR for stellar data…
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
14
Exoplanets
1 known planet
View in 3D
View this system in the 3D Orrery
Interactive Keplerian orbits, procedural planet textures, habitable zone.
| Planet | Radius | Mass | Period | Distance |
|---|---|---|---|---|
| 18 Del b | 12.50R⊕ | 9.21M♃ | 2.7yr | 249ly |
Habitable Zone
Size & Mass Comparison
About exoplanets — how we find them and which host stars you can observe
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.
Explore Nightbase
Related knowledge, tools, and stories — no observation planning required.
Arthur Eddington
1919 eclipse expedition confirming general relativity; first theory of stellar interiors; the Eddington limit
Biography
Delphinus
Mythology, bright stars, and deep-sky highlights.
Constellation
The Hertzsprung-Russell Diagram — Reading Stars Like a Map
The HR diagram turns the night sky into a physics map: every named star has a spot, every spot tells you mass, age, and fate. A guide for amateur observers.
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