Eta Cygni — Star in Cygnus
Observe
1Physical Properties
Magnitude
3.89
Spectral Type
K0III
giant
Star Color
Orange
(B-V 1.02)
Distance
135 ly
2Position & Identifiers
RA
19h 56m 18.4s
Dec
+35° 05' 00.0"
Constellation
Cygnus
(Cyg)
HR
7615
HIP
98110
HD
188947
SAO
69116
Bayer
Eta
Flamsteed
21 Cyg
Double Cat
13149
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | 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
Set a location in User Settings to see visibility data.
Best season
Jun – Aug
(peak: Jul)
5Survey Image
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Explore
7
Size Comparison
Querying VizieR for stellar data…
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
Discover
15Stellar Notes
AB CPM. B, 12v at 7". Other components optical.
0.035".
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.
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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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