54 Eridani — Double Star in Eridanus
Observe
1Physical Properties
Magnitude
4.32
Range
4.28 - 4.38
Period
30.0 days
Variable Type
Semi-Regular Variable (Late-type Giant)
Spectral Type
M4III
giant
Star Color
Red
(B-V 1.61)
Distance
408 ly
2Position & Identifiers
RA
04h 40m 26.5s
Dec
-19° 40' 18.0"
Constellation
Eridanus
(Eri)
HR
1496
HIP
21763
HD
29755
SAO
149818
Flamsteed
54 Eri
Variable ID
DM Eri
Double Cat
3380
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)
5Light Curve
6Multiple Star System
Separation
0.1″
Companion Mag
5.4
Position Angle
135°
Star Colors
A: Red
Discoverer
STN 9
Seen as double only in 1877 and 1923.
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
Discover
16Stellar Notes
SRb 4.28 - 4.36V, 30d.
17
Light Travel Time Machine
18
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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