Star profile

Omicron 1 Canis Majoris

Variable star

3D likeness based on its real data · class K · ~4,200 K

What is Omicron 1 Canis Majoris

Omicron-1 Canis Majoris is a colossal red supergiant, nearly four hundred times the Sun's radius and thirty-seven thousand times its light, tied to the distant Collinder 121 association in the southern reaches of Canis Major. It pulses slowly between magnitudes 3.8 and 4.0 without a clear rhythm. Despite being barely eighteen million years old, it is already destined to explode as a Type II supernova in a cosmically near future.

Where it is and when to see it

Omicron 1 Canis Majoris lies in the southern celestial hemisphere. It is visible to the naked eye under a dark sky. Its best month of the year is January, when it culminates around midnight.

From London it culminates about 14° above the horizon.
From New York it culminates about 25° above the horizon.
From Sydney it culminates about 80° above the horizon.

It can be seen from anywhere south of 66° N.

It ranks no. 10 in brightness among the 90 stars of Canis Major in our catalogue. To find it, start from Sirius, the brightest: it lies about 8° away (a fist at arm's length covers about 10°).

The light you see today left it about 330,000 years ago.

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Astronomical data for Omicron 1 Canis Majoris

Constellation: Canis Major
Apparent magnitude: 3.89
Distance: 326200.0 light years
Coordinates (J2000): RA 103.533° · Dec -24.184°
Catalogue: HIP 33152 · HD 50877

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Other stars in Canis Major

Canis Major has 90 stars in Stelvia's catalogue. Here are a few of them.

See all 90 stars in Canis Major