Pi Herculis — Star in Hercules
About Pi Her
Description
Pi Herculis is an orange giant of spectral type K3IIab at magnitude 3.16 in Hercules. Located about 377 light-years from Earth, it is a luminous evolved star with roughly 1,260 times the Sun's luminosity. Its surface temperature of about 4,100 K gives it a distinctly warm orange hue.
Observing Tips
Pi Her lies in the southeastern part of Hercules, outside the central Keystone asterism. It is a warm orange star that forms part of the kneeling hero's leg. Best observed from May through September when Hercules is high in the northern evening sky. It is easy to overlook among the many similarly bright stars in this large constellation.
History
Pi Herculis has no traditional proper name. Hercules is one of the most ancient constellations, recognized since Sumerian times. The constellation represents the great hero of Greek mythology performing his legendary labors, depicted as a kneeling figure in the sky.
Fun Facts
Pi Her is classified as a bright giant (luminosity class IIab), placing it between normal giants and true supergiants. Stars at this evolutionary stage are relatively rare because they pass through this phase quickly on their way to becoming even more luminous.
Observe
1Physical Properties
2Position & Identifiers
3How easy to spot?
| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | Easy | Medium+ |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
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5Survey Image
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Explore
7
Size Comparison
8
Compare Stars
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Spectral Classification
10
Hertzsprung-Russell Diagram
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
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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