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One of my favourite memories of July 2020 is standing outside on a clear summer evening looking at a beautiful comet, known as C/2020 F3, or Neowise, through a shaky pair of binoculars. It was a strange period, to say the least, but stargazing made me feel closer to friends and family who share this interest, who I couldn’t be with in person due to covid-19 restrictions. And glimpsing Neowise (pictured) was a true highlight for me during that time.

If you missed out on seeing it you won’t get another chance, as it won’t be back for a few thousand years. But don’t worry, because next month a different comet is set to grace our skies that could be brighter than Neowise – as long as it stays intact.

Since July, comet C/2023 A3, also known as Tsuchinshan–ATLAS, has been out of view as it rounded the sun. This object, which was visible through small telescopes earlier in the year, is expected to pop up again by mid-October. At this point, you might spy it with the naked eye at night.

Like all comets, Tsuchinshan–ATLAS is unpredictable. It was discovered in February 2023 by astronomers at an observatory in Sutherland, South Africa. However, it was later found to have been spotted earlier than that, but not identified as a new comet, at the Purple Mountain Observatory in Nanjing, China, in early January.

At first, it was being called the comet of the century. This was because its peak brightness was predicted to exceed that of Jupiter at its brightest, only being outshone by a full moon.

Now, as we have learned more about the comet and its trajectory, the expected brightness has been revised down. It all depends on how active the comet is, but optimistic predictions are that it will shine on a par with Vega, one of the brightest stars in the night sky. If this is the case, it will be clearly visible with the naked eye. But others think it will and fall apart before it reappears, meaning it won’t be visible at all.

I will keep my fingers crossed that comet Tsuchinshan–ATLAS does make an appearance. If so, you should be able to see it after sunset in the west from around 15 October, or perhaps even sooner. It will be between the constellations Virgo and Serpens. If it is visible, you should be able to see it from anywhere in the world. But use software like Stellarium Web to check exactly where the comet will pop up in the place you live, and keep an eye on updates about its brightness.

This time round, I am expecting to be in my own state of semi-lockdown, since my first child is due in September. I will be leaving this column in the capable hands of Leah Crane, 91av‘s expert in all things space. And I won’t stop stargazing. I plan to spend some of my sleepless evenings watching the sky in the knowledge that fellow enthusiasts will be doing the same.

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