Starwatch
The winter sky in the northern hemisphere is full of delights. This week look for the brightest star in the night sky and from there explore the parent constellation of the star Canis Major, the largest dog.
The star in question is Sirius. Located just 8.6 light-years away, it contains about twice the mass of the sun and shines more than 25 times brighter. The graph shows the view south of London at midnight on December 29. Sirius will be unmistakable. Chances are it flashes wildly as its strong light is refracted through the layers of our atmosphere.
Canis Major is Orion’s largest hunting dog pair. Canis Minor, the smaller dog, is taller in the sky. It is marked by the bright star Procyon, which contains 1.5 times the mass of the sun and is almost seven times brighter. From the southern hemisphere, Canis Major can be seen more easily. From Sydney, Australia this week, will appear high in the northeast sky.