Z Eridani — Variable Star in Eridanus
Excellent (63/100)
Observe
1Physical Properties
Magnitude
6.90
Range
6.17 - 7.18
Period
74 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
M4III
giant
Star Color
Red
(B-V 1.56)
2Position & Identifiers
RA
02h 47m 56.0s
Dec
-12° 27' 38.0"
Constellation
Eridanus
(Eri)
HR
832
HIP
13064
HD
17491
SAO
148612
Variable ID
Z Eri
Querying VizieR catalog...
3How easy to follow?
Magnitude
6.2 – 7.2 mag
Amplitude
1.0 mag
Period
74 d
Type
SRB
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard | V. hard | Imp. |
| 50 mm finder 50mm finder | Medium+ | Medium+ | Medium+ |
| 150 mm telescope 150mm scope | Medium+ | Medium+ | Medium+ |
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
Sep – Nov
(peak: Oct)
5Survey Image
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6Light Curve
7Comparison Stars for Z Eri (6.2–7.2)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
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
SRb 7.0 - 8.63p, 80d. Secondary cycle 746d.
Wolf 630 group.
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
Eridanus
Mythology, bright stars, and deep-sky highlights.
Constellation
