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42 Librae — Star in Libra

Magnitude 5.0m Star Libra (Lib) Visible
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1Physical Properties

Magnitude 4.96
Spectral Type K3IIICN1 giant
Star Color Red (B-V 1.33)
Distance 67 ly

2Position & Identifiers

RA 15h 40m 16.9s
Dec -23° 49' 05.0"
Constellation Libra (Lib)
HR 5824
HIP 76742
HD 139663
SAO 183686
Flamsteed 42 Lib
SIMBAD

3How easy to spot?

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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Medium Medium 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 Apr – Jun (peak: May)

5Survey Image

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6

Size Comparison

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7

Compare Stars

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

Discover

14Stellar Notes

Occultation diam. = 0.0022".
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.

2 Sco
Medium
Tight double — a rewarding split at 2.0″
Double Star mag 4.59 3.4° Scorpius
Kappa Lib
Easy
Cool red giant
Star mag 4.74 4.2° Libra
NGC 5903
Medium+
Elliptical galaxy
Galaxy mag 11.5 5.0° Libra
NGC 5897
Easy
Globular cluster — dense ball of ancient stars
Globular Cluster mag 8.6 6.0° Libra
IC 4592
Medium+
Reflection nebula around a bright star
Reflection Nebula mag 3.90 8.6° Scorpius
Show on Map

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