Australasian Science: Australia's authority on science since 1938

September 2012 guide and star chart

By David Reneke

Your guide to the night skies this month.

The full text of this article can be purchased from Informit.

Someone who once tried to count them said there were more stars in the Universe than heartbeats for every human who ever lived! Now that’s a big number. Have you ever wondered where the names of some of the stars come from?

There are billions and billions of stars but only some 6,000 or so are visible to the naked eye. Of those only a handful of the brightest have proper names like Sirius or Betelgeuse, the rest are simply given letters of the Greek alphabet.

Sirius is well known because it is the brightest star in the night sky. It was equally important to the ancient Egyptians who associated it with their goddess Isis. And you’ve probably heard of Betelgeuse because of that movie even if it’s often mispronounced as ‘Beetle-juice’ right? Even our Australian aborigines have legends about the stars and constellations in their Dreamtime.

Heading towards Christmas we’re also heading into the best sky watching period, and things are going to get interesting. So, grab your telescope, I’ll grab mine, and I’ll meet you on the lawn.

Saturn makes its way towards the western horizon this month with Mars below. The bright star Spica (Virgo) can be found sitting to the left of Saturn. On the 18th the crescent Moon joins the pair. Then on the 30th, Mercury can be seen below Spica, with Saturn above and to the right.

Rising around midnight in the...

The full text of this article can be purchased from Informit.

David Reneke is a feature writer for major Australian publications including Australasian Science magazine and a science correspondent for ABC and commercial radio. Get David’s free astronomy newsletter at