Phi Herculis — Star in Hercules
Observe
1Physical Properties
Magnitude
4.26
Range
4.24 - 4.25
Period
7.0 days
Variable Type
ACV:
Spectral Type
B9p:Mn:
Star Color
Blue-white
(B-V -0.07)
Distance
163 ly
2Position & Identifiers
RA
16h 08m 46.2s
Dec
+44° 56' 06.0"
Constellation
Hercules
(Her)
HR
6023
HIP
79101
HD
145389
SAO
45911
Bayer
Phi
Flamsteed
11 Her
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | 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
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Best season
Apr – Jun
(peak: May)
5Survey Image
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Explore
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
Alpha CV?, 4.23 - 4.27V, amp. 0.015U, 7.832d, symmetric light curve.
560.5d, K 2.4k/s, V0 -16.8k/s, asini 16.3. Unresolved by speckle interferometry 1986.45.
HgMn star.
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.
IC 1153
Bright spiral galaxy
Galaxy
mag 12.72
3.8°
Hercules
30 Her
Mira-type variable, range 4.3–6.3
Variable Star
mag 5.04
4.7°
Hercules
42 Her
Cool red giant
Double Star
mag 4.90
6.5°
Hercules
NGC 6229
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 9.4
7.1°
Hercules
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Article
Hercules
Mythology, bright stars, and deep-sky highlights.
Constellation
