Gamma Lupi — Double Star in Lupus
About Gamma Lup
Description
Gamma Lupi is a blue subgiant of spectral type B2IV at magnitude 2.78, the third brightest star in Lupus. Located about 420 light-years from Earth, it has a luminosity of roughly 8,500 times solar. It is a spectroscopic binary with a period of about 2.8 days.
Observing Tips
Gamma Lup lies in the body of Lupus, between Alpha Lup and the stars of Centaurus. It is a blue-white star in a rich part of the southern Milky Way. Only visible from the southern hemisphere and low northern latitudes. Best observed May through July.
History
Gamma Lupi has no traditional proper name. Like the other bright stars of Lupus, it is a member of the Scorpius-Centaurus OB association and formed relatively recently in astronomical terms.
Fun Facts
Gamma Lup's short-period spectroscopic binary means its two components orbit incredibly close together — completing a full orbit in less than 3 days, far faster than Mercury orbits the Sun.
Observe
1Physical Properties
2Position & Identifiers
3How easy to split?
| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | V. hard | V. hard | V. hard |
| 150 mm Newton 150mm Newt. | Hard | Hard | Hard |
| Celestron C8 (203 mm SCT) C8 203mm | Hard | Hard | Hard |
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
5Multiple Star System D: optical
Separation over time
Apparent separation over time, computed from ORB6 orbital elements. Steep curves indicate fast-changing pairs — catch them while they're splittable.
Eyepiece View
A: 2.8 · B: 3.5 · Sep: 0.8″ · PA: 275° · N up, E right
Unresolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″
Explore
7
Size Comparison
8
Compare Stars
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Spectral Classification
10
Hertzsprung-Russell Diagram
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
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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