Tau Eridani — Star in Eridanus
HIP 14146; Tau3 Eridani; 11 Eridani
Observe
1Physical Properties
Magnitude
4.09
Spectral Type
A4IV
subgiant
Star Color
Yellow-white
(B-V 0.16)
Distance
55 ly
2Position & Identifiers
RA
03h 02m 23.5s
Dec
-23° 37' 28.0"
Constellation
Eridanus
(Eri)
HR
919
HIP
14146
HD
18978
SAO
168249
Bayer
Tau3
Flamsteed
11 Eri
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
Set a location in User Settings to see visibility data.
Best season
Oct – Dec
(peak: Nov)
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
Discover
15Stellar Notes
UMa stream.
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.
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Article
Eridanus
Mythology, bright stars, and deep-sky highlights.
Constellation
