Looking east
The Pleiades
We start our tour by looking low in the sky, just above the northeastern horizon. There you will see – as long as there are no trees, hills or buildings in the way – a knot of blue-white stars, roughly the size of your thumbnail held at arm’s length. This is one of the most famous star clusters in the sky: the Pleiades.
This beautiful spill of stars – which is only 444 lightyears from Earth, making it one of the closest star clusters to us – is famously known as The Seven Sisters because, although it contains many hundreds of stars, its seven brightest members can be seen with the naked eye, looking like a miniature version of the Plough. If you have binoculars you will be able to see many dozens of fainter stars dotted around the brightest ones. Whenever stargazers see the Pleiades for the first time in autumn, they know that winter isn’t far away. Then the Pleiades will shine high in the sky all through the night, above and to the right of Orion.
The Double Cluster
Look to the upper left of the Pleiades, halfway between the ‘W’ of constellation Cassiopeia, the Queen and the upside down ‘Y’ of Perseus, the Hero and you’ll see a vague, smudgy… something out of the corner of your eye. This is actually two star clusters (NGC 884 and NGC 869) sparkling together side by side, known, appropriately, as the Double Cluster.
Through your binoculars the Double Cluster will be resolved into two distinct star clusters, looking like piles of salt or sugar grains, so close they are almost touching. The clusters are a gravitationally bound pair. Around 8,100 lightyears away, they are separated by a few hundred lightyears.
The Andromeda Galaxy
Look to the right of the Double Cluster, approximately halfway between it and the Great Square of Pegasus and you’ll see a large, misty smudge with a roughly oval shape. This is M31, the Andromeda Galaxy, a huge spiral galaxy.
M31 is the closest spiral galaxy to our Milky Way, but it’s still so far away that its light takes around 2.5 million years to reach us. This makes M31 famous in astronomy as a distant object that is visible to the naked eye. Through your binoculars M31 is revealed to be a lensshaped haze of light, noticeably brighter in the centre, that covers an area of night sky that’s roughly six times as large as the full Moon.