Last week, we discussed the Dog Star, Sirius, the sky’s brightest star. Orbiting Sirius is a faint companion, a tiny star known informally as the Pup.

This week’s first small-telescope target is Sirius B, the companion to the night sky’s brightest star, Alpha (α) Canis Majoris. American telescope-maker Alvin Graham Clark discovered that ...

The brightest star in the nighttime sky, Sirius, or the Dog Star, greatly outshines its white dwarf companion, Sirius B. At 8.6 light-years away, Sirius B is the nearest known white dwarf star to ...