Eta Scorpii — Double Star in Scorpius
Observe
1Physical Properties
Magnitude
3.33
Spectral Type
F5IV
subgiant
Star Color
Yellow-white
(B-V 0.41)
Distance
73 ly
2Position & Identifiers
RA
17h 12m 09.2s
Dec
-43° 14' 21.0"
Constellation
Scorpius
(Sco)
HR
6380
HIP
84143
HD
155203
SAO
227707
Bayer
Eta
Querying VizieR catalog...
3How easy to split?
Primary
3.3 mag
Companion
11.2 mag
Separation
591.8″
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| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | Hard+ | Hard | V. hard+ |
| 150 mm Newton 150mm Newt. | Medium+ | Medium | Hard+ |
| Celestron C8 (203 mm SCT) C8 203mm | Medium+ | Medium+ | Medium |
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
May – Jul
(peak: Jun)
5Multiple Star System
Separation
591.8″
Companion Mag
11.2
Position Angle
129°
Star Colors
A: Yellow-white
Discoverer
GAT 21
Eyepiece View
15x
Dawes: 1.9″
TFOV: 3.3°
Realistic = true angular size
A: 3.3 · B: 11.2 · Sep: 591.8″ · PA: 129° · N up, E right
Resolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″
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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
Discover
15Stellar Notes
Hyades group.
Also classified F2V.
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 6322
Rich open cluster
Open Cluster
mag 6.0
1.2°
Scorpius
V861 Sco
Eclipsing binary, period 7.8d
Variable Star
mag 6.15
3.8°
Scorpius
NGC 6388
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 6.9
4.6°
Scorpius
Sargas
HIP 86228; Theta Scorpii
Easy double, sep 6.5″
Double Star
mag 1.87
4.6°
Scorpius
V918 Sco
Hot blue O-type star
Double Star
mag 5.47
6.5°
Scorpius
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