This month, look for the star, Procyon, the lucida of the constellation of Canis Minor (the Little Dog) and the seventh brightest star in the sky. If you were born in 2005, then Procyon is your birthday star this year because the light of Procyon you see tonight left the star 11 years ago. The name Procyon comes from Greek and means Before the Dog. This refers to the fact that in mid-latitudes, Procyon rises shortly before Sirius, the Dog Star.

Procyon has twice the diameter of our sun due to its 70% greater mass. Its greater temperature and diameter combine to make Procyon over seven times more luminous than the Sun. Procyon has consumed enough of its hydrogen that it can now fuse helium. In several tens of millions of years, just a blip of time for our sun, Procyon will expand into a red giant star.  

White dwarf companion stars orbit both Procyon and Sirius. White dwarfs are stars that have consumed their supply of nuclear fuel. Without fusion to support them, gravity has compressed them into spheres the size of planets, or about 100 times smaller that they use to be. This means a cubic centimeter of white dwarf weighs about a ton. So imagine your car fitting on a teaspoon.

You’ll find Procyon half way up in the south-southeast early February nights.