About Phi Lup
Description
Phi Lupi is a K-type giant of spectral class K4 III about 275 light-years away in the southern constellation Lupus. It shines at magnitude 3.56 and is a member of the Upper Centaurus-Lupus stellar association of young massive stars. Phi Lupi is a known spectroscopic binary with a faint close companion, though the primary dominates the total light output.
Observing Tips
Phi Lupi is best seen from southern latitudes. It lies in the northern part of Lupus, near the boundary with Centaurus. A fine naked-eye star with a warm orange color. Best observed April through August from the southern hemisphere.
History
Phi Lupi retains its Bayer designation in modern catalogs.
Fun Facts
The Upper Centaurus-Lupus association, which includes Phi Lupi and many other prominent stars of the region, is one of the closest and best-studied OB associations. Its age of 15-17 million years makes it a prime laboratory for understanding how young massive-star populations evolve.
Observe
1Physical Properties
2Position & Identifiers
3How easy to spot?
| 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 |
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
5Survey Image
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Explore
7
Size Comparison
8
Compare Stars
9
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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