Theta Herculis — Star in Hercules
Observe
1Physical Properties
Magnitude
3.86
Spectral Type
K1IIa CN2
supergiant
Star Color
Red
(B-V 1.35)
Distance
752 ly
2Position & Identifiers
RA
17h 56m 15.2s
Dec
+37° 15' 02.0"
Constellation
Hercules
(Her)
HR
6695
HIP
87808
HD
163770
SAO
66485
Bayer
Theta
Flamsteed
91 Her
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | 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
May – Jul
(peak: Jun)
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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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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15Stellar Notes
Possibly 5 yr. period in He 10830 emission.
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.
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Article
Hercules
Mythology, bright stars, and deep-sky highlights.
Constellation
