Theta Librae — Double Star in Libra
Observe
1Physical Properties
Magnitude
4.15
Spectral Type
G8.5IIIb
bright giant
Star Color
Orange
(B-V 1.02)
Distance
91 ly
2Position & Identifiers
RA
15h 53m 49.5s
Dec
-16° 43' 46.0"
Constellation
Libra
(Lib)
HR
5908
HIP
77853
HD
142198
SAO
159563
Bayer
Theta
Flamsteed
46 Lib
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | 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
Apr – Jun
(peak: May)
5Multiple Star System
Separation
0.1″
Companion Mag
5.1
Position Angle
-1°
Star Colors
A: Orange
Discoverer
OCC 985
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7
Size Comparison
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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
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15
Light Travel Time Machine
16
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.
IC 4592
Reflection nebula around a bright star
Reflection Nebula
mag 3.90
5.1°
Scorpius
Jabbah
HIP 79374; Nu Scorpii; 14 Scorpii
Easy double, sep 41.4″
Double Star
mag 4.01
5.1°
Scorpius
M80
NGC 6093
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 7.2
8.3°
Scorpius
NGC 5915
Barred spiral galaxy
Galaxy
mag 12.0
8.6°
Libra
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