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Pi Aurigae — Star in Auriga

Magnitude 4.3m Star Auriga (Aur) Visible
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Observe

1Physical Properties

Magnitude 4.26
Range 4.24 - 4.40
Variable Type Slow Irregular Variable
Spectral Type M3II bright giant
Star Color Red (B-V 1.72)
Distance 1,087 ly

2Position & Identifiers

RA 05h 59m 56.1s
Dec +45° 56' 13.0"
Constellation Auriga (Aur)
HR 2091
HIP 28404
HD 40239
SAO 40756
Bayer Pi
Flamsteed 35 Aur
Variable ID Pi Aur
SIMBAD

3How easy to spot?

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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Medium+ Medium+ Medium
50mm finder Easy Easy Easy
150mm scope Easy Easy Easy
Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

4Visibility

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Best season Nov – Jan (peak: Dec)

5Survey Image

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Explore

7

Size Comparison

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8

Compare Stars

9

Spectral Classification

10

Hertzsprung-Russell Diagram

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Read: The Hertzsprung-Russell Diagram — Reading Stars Like a Map
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

Lc 4.24 - 4.34V. Radio emission at 2.85cm indicates mass loss.
Large infrared excess.
Ultraviolet FeII emission.
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.

Menkalinan
Beta Aur
Easy
Bright naked-eye star, mag 1.9
Star mag 1.90 1.0° Auriga
NGC 2126
Easy
Open cluster
Open Cluster mag 10.0 4.0° Auriga
Psi Aur
HIP 30520; Psi1 Aurigae; 46 Aurigae
Medium+
Semi-regular variable, range 4.8–5.7
Variable Star mag 4.91 5.4° Auriga
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