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Alpha Librae — Star in Libra

HIP 72603; Alpha1 Librae; 8 Librae

Magnitude 5.2m Star Libra (Lib) Visible
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1Physical Properties

Magnitude 5.15
Spectral Type F4IV subgiant
Star Color Yellow-white (B-V 0.41)
Distance 65 ly

2Position & Identifiers

RA 14h 50m 41.2s
Dec -15° 59' 50.0"
Constellation Libra (Lib)
HR 5530
HIP 72603
HD 130819
SAO 158836
Bayer Alpha1
Flamsteed 8 Lib
SIMBAD Wikipedia

3How easy to spot?

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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Medium Hard+ Hard
50mm finder Easy Easy Easy
150mm scope Easy Easy Easy
Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

4Visibility

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Best season Mar – May (peak: Apr)

5Survey Image

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6

Size Comparison

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7

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8

Spectral Classification

9

Hertzsprung-Russell Diagram

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Read: The Hertzsprung-Russell Diagram — Reading Stars Like a Map
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

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14Stellar Notes

CPM with HR 5531 at 231". Component A, HR 5531, is the suspected occultation double, 3.4, 3.8, sep. 0.01".
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.

Zuben Elgenubi
HIP 72622; Alpha2 Librae; 9 Librae
Easy
Easy double, sep 230.8″
Double Star mag 2.75 0.1° Libra
NGC 5796
Hard
Elliptical galaxy
Galaxy mag 13.0 2.2° Libra
Zuben El Akribi
HIP 73473; Delta Librae; 19 Librae
Medium+
Eclipsing binary, period 2.3d
Variable Star mag 4.92 7.9° Libra
NGC 5897
Easy
Globular cluster — dense ball of ancient stars
Globular Cluster mag 8.6 8.1° Libra
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