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THE first week of the new year brings us a new moon, and the perfect time to hunt for the fainter objects in the night sky. I will be looking to spot a galaxy called Triangulum, or M33, which can be seen from anywhere in the world with dark skies this time of year.

The most famous galaxy that can be viewed from Earth with the naked eye is Andromeda, our neighbouring one, which is 2.5 million light years away. We have previously looked at how to spot the Andromeda galaxy (14 December 2019), and this is often cited as the most distant object from us that is visible with the naked eye. But M33 is even further away and can sometimes be seen with no assistance, although you need to be in a place with exceptionally dark skies.

Triangulum is a spiral galaxy 2.7 million light years from Earth. It is the third-largest member of the local group of galaxies, after Andromeda and our own, the Milky Way. It was first catalogued by Charles Messier in 1764, when it was named Messier 33, though it may well have been spotted by someone else before this.

It was thought to be a nebula – a huge cloud of gas and dust – in our own galaxy. But in the 1920s, had characteristics that enabled him to estimate their distance. From this, he demonstrated that Triangulum was a galaxy in its own right.

It is so faint because it boasts only about 40 million stars, compared with the trillion or so in Andromeda. As a result, Triangulum can only be seen with the naked eye from places with excellent viewing conditions. If you don’t have access to a dark sky reserve, you can try looking with binoculars. Either way, get away from any sources of light and let your eyes adjust for as long as possible before looking for it.

Triangulum sits near the Andromeda galaxy in the night sky. First, find the constellation of Triangulum, a small one between the Andromeda constellation and Taurus, which we have previously found (2 November 2019). To do this, draw a line between the bright star Aldebaran in Taurus and the small bright cluster of stars, the Pleiades, also in Taurus, and continue this in the direction of Andromeda until you see three stars forming a small triangle. These are Gamma Trianguli and Beta Trianguli, close to each other, with Mothallah making up the third point of the triangle.

Next, find the Triangulum galaxy. To locate it, look between Mothallah and Mirach, the bright star in the centre of the constellation Andromeda. The galaxy sits about a third of the way from Mothallah to Mirach. It should look like a fuzzy blob, roughly the shape of an egg.

Remember, you will need extremely dark skies to see it, and it is tricky to find, so don’t worry if you don’t pick it out immediately. Good luck!

For other projects visit newscientist.com/maker.