Eta Arietis — Star in Aries
Observe
1Physical Properties
Magnitude
5.27
Spectral Type
F5V
Star Color
Yellow-white
(B-V 0.43)
2Position & Identifiers
RA
02h 12m 48.1s
Dec
+21° 12' 39.0"
Constellation
Aries
(Ari)
HR
646
HIP
10306
HD
13555
SAO
75204
Bayer
Eta
Flamsteed
17 Ari
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium | Hard+ | 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
Set a location in User Settings to see visibility data.
Best season
Sep – Nov
(peak: Oct)
5Survey Image
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Explore
6
Size Comparison
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7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
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10
Stellar Lifecycle
11
Blackbody Spectrum
12
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
13
Stellar Fusion
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
Aries
Mythology, bright stars, and deep-sky highlights.
Constellation
