Our winter sky

by Geoffrey Lindop, 17th January 2024
Caerlaverock Castle | Dumfries & Galloway
Our winter sky

As the chilly embrace of winter settles over the picturesque landscapes of the South of Scotland, a celestial spectacle unfolds above. The night sky becomes an awe-inspiring canvas, adorned with twinkling stars, constellations, and cosmic wonders waiting to be explored. Night sky expert Geoffrey Lindop has all the tips on what to look out for in the coming months and how to make the most of our dark winter skies.

The winter triangle

Three very bright stars, Betelgeuse, Sirius and Procyon, form the Winter Triangle, that dominates the southern sky over the winter months.

The first of these, Betelgeuse sits in the constellation of Orion. A constellation is a group of stars that resemble something, in this case Orion looks like a hunter. The Winter Triangle features three stars from different constellations and is called an asterism.

The winter triangle is formed by three bright stars easy to spot in our night skies.

Betelgeuse in Orion

Betelgeuse is 17 times larger than our Sun and encompasses a space the size of the entire orbit of Mars. It is in a class of stars that astronomers call Red Giants. The starlight we see is produced by a star’s conversion of hydrogen into helium. Because Red Giants are so massive, they burn up their hydrogen far quicker than smaller stars, such as our Sun. And while it may be large, Betelgeuse is only 10 million years old, meaning it appeared about the same time as apes started to feature on Earth. Yet Betelgeuse is using up its hydrogen so fast it is likely to die in a massive explosion soon – maybe tonight but more likely within the next 100,000 years!

Sirius in the Great Dog

Sitting below Orion is the constellation of Canis Major, commonly called the Great Dog. Sirius, the brightest star in the sky, is also known as the Dog Star because of its location in the Great Dog. It appears as a single source of light to us but it is in fact two stars that orbit each other every 50 years.

Procyon in the Little Dog

Similarly Procyon is a double star in the constellation of Canis Minor, the Little Dog. These two stars orbit each other about every 41 years. It takes the starlight from Procyon 11.46 years to reach the Earth, whereas we see Sirius as it was 8.6 years ago. By comparison the light from the Sun reaches our eyes in only eight minutes.

See more with binoculars

All the above mentioned can easily be seen with the naked eye, but telescopes help the observer see fainter objects. You don’t need to have an expensive telescope to enjoy astronomy, even a modest pair of binoculars will reveal interesting objects.

An object easily seen with binoculars is the asteroid Vesta. It appears as a star-like dot of light. Asteroids are little more than lumps of rock that orbit the Sun mostly between the orbits of Mars and Jupiter. Vesta, for example, has a diameter roughly the same as the distance between Edinburgh and London. In December Vesta is about 1.5 times as far away as the Sun and is visible throughout the winter initially in the constellation of Gemini, before moving into Taurus. As the weeks go by it gets fainter and more distant.

Taking photos of the night sky

If you want to capture some pictures, you don’t need an expensive camera to capture the night sky. It is possible to have some limited success with the camera on a mobile phone. But a camera with a big lens and mounted on a tripod is the better option. Try taking the Moon against the foreground of a building or landscape feature. Better still wait for the Moon to move close to a bright star or one of the planets.

Download an app

Do download a planetarium app for your mobile device to show you where to look. Some planetarium apps are free to download. I use Stellarium but there are many to choose from that are equally good.

You can learn more with our Top Tips for stargazing and be sure to visit our Dark Skies section for all the information for inspiration and to plan your next visit.

Geoffrey has written a guide to the night sky to assist business owners in the south of Scotland, available to purchase at various locations or directly from the publisher.

We are grateful to Geoffrey for also producing a monthly night-by-night guide to the skies above us, so you can check out what there is to see throughout the upcoming winter months. And we will have more from Geoffrey on what to see in the night sky through the seasons!