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Iota Canis Majoris — Star in Canis Major

Magnitude 4.4m Star Canis Major (CMa) Visible
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1Physical Properties

Magnitude 4.37
Range 4.36 - 4.40
Period 1.9 hours
Variable Type Beta Cephei (Pulsating)
Spectral Type B3II bright giant
Star Color Blue-white (B-V -0.07)
Distance 652 ly

2Position & Identifiers

RA 06h 56m 08.2s
Dec -17° 03' 15.0"
Constellation Canis Major (CMa)
HR 2596
HIP 33347
HD 51309
SAO 152126
Bayer Iota
Flamsteed 20 CMa
Variable ID Iot CMa
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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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

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15Stellar Notes

Beta C 4.36 - 4.40v, 0.08:d.
Sirius group? Member of the local association (Pleiades group); possible member Collinder 121 (#26).
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.

NGC 2296
Hard+
Elliptical galaxy
Galaxy mag 13.0 1.8° Canis Major
Mu CMa
Easy
Colorful double, sep 2.8″
Double Star mag 5.00 3.0° Canis Major
15 CMa
Easy
Hot blue O-type star
Star mag 4.83 3.2° Canis Major
M41
NGC 2287
Easy
Rich open cluster
Open Cluster mag 4.5 4.3° Canis Major
R CMa
Medium
Eclipsing binary, period 1.1d
Variable Star mag 5.70 5.6° Canis Major
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