Epsilon Lupi — Double Star in Lupus
Observe
1Physical Properties
Magnitude
3.37
Range
3.36 - 3.38
Period
4.6 days
Variable Type
Luminous Blue Variable
Spectral Type
B2 IV/V
subgiant
Star Color
Blue
(B-V -0.18)
Distance
499 ly
2Position & Identifiers
RA
15h 22m 40.9s
Dec
-44° 41' 22.0"
Constellation
Lupus
(Lup)
HR
5708
HIP
75264
HD
136504
SAO
225712
Bayer
Epsilon
Variable ID
Var?
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | Easy | 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
Apr – Jun
(peak: May)
5Light Curve
6Multiple Star System Triple
Components
3 (triple)
Component IDs
AB
Separation
0.2″
Companion Mag
5.0
Position Angle
6°
Star Colors
A: Blue
B: Blue-white
Discoverer
COP 2
AB binary. Combined mag., colors. C, 9v at 27" probably optical.
Separation over time
Period: 736.7 y
Eccentricity: 0.808
Now: 0.24", PA 3°
+ 0.09" in 5 years
Apparent separation over time, computed from ORB6 orbital elements. Steep curves indicate fast-changing pairs — catch them while they're splittable.
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
Var? Amp. 0.015b.
Primary of visual system, 4.5598d, K 56.1k/s, V0 +7.9k/s, msin3i 0.404, asini 3.40.
Upper Cen group of Sco-Cen assoc.
Comp. C, -26k/s.
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.
HIP 76371
Tight double — a rewarding split at 2.1″
Double Star
mag 4.54
2.4°
Lupus
Pi Lup
HIP 73807; Pi Lupi
Tight double — a rewarding split at 1.6″
Double Star
mag 4.72
3.9°
Lupus
GG Lup
Eclipsing binary, period 1.8d
Variable Star
mag 5.59
4.0°
Lupus
NGC 5927
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 8.3
6.0°
Lupus
NGC 5670
Bright spiral galaxy
Galaxy
mag 11.96
8.4°
Lupus
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