Seeing Double

Find the constellation of The Plough (also known as the Big Dipper, the Saucepan or the Wagon depending on which country you are in) and take a look at the second star of the “handle” of the saucepan; you should be able to make out a second, fainter, “companion” star. The two stars are sometimes called the "Horse and Rider," in fact the ability to resolve the two stars with the naked eye is often quoted as a test of eyesight.

Many of the stars in the sky are in fact double stars (or even triple or quadruple stars), although not as easy to see as the example above. Many, however, can be seen in a small telescope or even in a pair of binoculars.

What is particularly interesting (and often quite spectacular) is the fact that many of the double stars are often two different colours, yellow and green, or orange and blue for example.

Here are a couple of double stars relatively easy to find.

The Pole star (Polaris) is a very easy double and can be seen in any small instrument
Rigel the bright star bottom right in the constellation of Orion is also easy

In another post we’ll look at some double stars a little more difficult to find, but when you find them or show them to others you will undoubtedly here “wow”!

Photo credit: Wikipedia