Eta Capricorni — Double Star in Capricornus
Observe
1Physical Properties
Magnitude
4.84
Spectral Type
A5V
Star Color
Yellow-white
(B-V 0.17)
Distance
59 ly
2Position & Identifiers
RA
21h 04m 24.3s
Dec
-19° 51' 18.0"
Constellation
Capricornus
(Cap)
HR
8060
HIP
104019
HD
200499
SAO
189986
Bayer
Eta
Flamsteed
22 Cap
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | Medium | 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
Jul – Sep
(peak: Aug)
5Multiple Star System
Separation
0.2″
Companion Mag
7.4
Companion Sp
F2V
Position Angle
246°
Star Colors
A: Yellow-white
B: Yellow-white
Discoverer
FIN 328
Separation over time
Period: 27.9 y
Eccentricity: 0.409
Now: 0.23", PA 209°
-0.07" in 5 years
Apparent separation over time, computed from ORB6 orbital elements. Steep curves indicate fast-changing pairs — catch them while they're splittable.
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
Discover
14
Light Travel Time Machine
15
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.
24 Cap
Cool red giant
Double Star
mag 4.50
5.2°
Capricornus
M73
NGC 6994
Open cluster
Open Cluster
mag 9.0
7.3°
Aquarius
M72
NGC 6981
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 9.4
7.8°
Aquarius
Saturn nebula
NGC 7009
Small bright planetary nebula
Planetary Nebula
mag 8.0
8.5°
Aquarius
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