About Pi Ori
Description
Pi-4 Orionis is a B-type subgiant of spectral class B1.5 IV about 1,300 light-years away. It shines at magnitude 3.72 and is part of the chain of shield stars in Orion's western edge. Pi-4 has an estimated mass of 12 solar masses and is a member of the Orion OB1 stellar association. It is an eclipsing binary with a close companion producing small photometric dips.
Observing Tips
Pi-4 Ori forms part of the visible arc of Orion's shield. The eclipses are very shallow (a few hundredths of a magnitude) and not detectable by eye. Binoculars show a clean blue-white star in a rich stellar field. Best observed November through March.
History
Pi-4 Orionis has no widely-used traditional name in current IAU catalogs.
Fun Facts
The Pi-series stars of Orion (Pi-1 through Pi-6) form one of the sky's largest Bayer-designated series belonging to a single asterism — all lie along the shield of Orion, and all are bright young O/B-type members of the Orion OB1 association.
Observe
1Physical Properties
2Position & Identifiers
3How easy to spot?
| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | Medium+ | 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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