Pi Gruis — Variable Star in Grus
HIP 110478; Pi Gruis
Excellent (66/100)
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1Physical Properties
Magnitude
6.62
Range
5.31 - 7.01
Period
196 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
S5,7e
Star Color
Deep ruby red
(B-V 2.01)
2Position & Identifiers
RA
22h 22m 43.9s
Dec
-45° 56' 52.0"
Constellation
Grus
(Gru)
HR
8521
HIP
110478
HD
212087
SAO
231105
Bayer
Pi
Variable ID
Pi1 Gru
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3How easy to follow?
Magnitude
5.4 – 6.7 mag
Amplitude
1.3 mag
Period
195.5 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard+ | V. hard | V. hard |
| 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
Jul – Sep
(peak: Aug)
5Survey Image
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6Light Curve
7Comparison Stars for Pi Gru (5.4–6.7)
Nearby stable stars for estimating brightness (AAVSO)
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8
Size Comparison
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9
Compare Stars
10
Spectral Classification
11
Hertzsprung-Russell Diagram
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12
Stellar Lifecycle
13
Blackbody Spectrum
14
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
15
Stellar Fusion
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16Stellar Notes
Component A of visual double, SRb 5.41 - 6.70V, about 150d.
Companion G0V. B-V for combined light +2.10. Since 1900 no relative motion of components observed.
Probable Hyades group.
IR shell emission associated with carbon-rich material.
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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Mythology, bright stars, and deep-sky highlights.
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