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Gamma Herculis — Star in Hercules

Magnitude 3.8m Star Hercules (Her) Visible
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1Physical Properties

Magnitude 3.75
Spectral Type A9III giant
Star Color Yellow-white (B-V 0.27)
Distance 193 ly

2Position & Identifiers

RA 16h 21m 55.2s
Dec +19° 09' 11.0"
Constellation Hercules (Her)
HR 6095
HIP 80170
HD 147547
SAO 102107
Bayer Gamma
Flamsteed 20 Her
Double Cat 10022
SIMBAD

3How easy to spot?

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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Easy Medium+ Medium+
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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7

Size Comparison

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8

Compare Stars

9

Spectral Classification

10

Hertzsprung-Russell Diagram

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

ADS 10022B, 9.58v, optical.
11.9d.
Hyades group.
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 6181
Medium
Bright spiral galaxy
Galaxy mag 11.9 2.5° Hercules
NGC 6210
Easy
Small bright planetary nebula
Planetary Nebula mag 9.0 7.0° Hercules
Blaze Star
HR 5958
Medium+
Mira-type variable, range 2.0–10.8
Variable Star mag 10.00 8.5° Corona Borealis
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