Mu Eridani — Star in Eridanus
Observe
1Physical Properties
Magnitude
4.02
Spectral Type
B5IV
subgiant
Star Color
Blue-white
(B-V -0.15)
2Position & Identifiers
RA
04h 45m 30.1s
Dec
-03° 15' 17.0"
Constellation
Eridanus
(Eri)
HR
1520
HIP
22109
HD
30211
SAO
131468
Bayer
Mu
Flamsteed
57 Eri
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
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Best season
Oct – Dec
(peak: Nov)
5Survey Image
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7
Size Comparison
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8
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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
B3, A3, 7.3589d, K 19.4k/s, V0 +23.3k/s, asini 1.90.
Member of the local association (Pleiades group); Cas-Tau OB1.
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
