Comet C/2023 A3 — otherwise known as Tsuchinshan-ATLAS or Comet A3 — has already made its grand entrance, dazzling stargazers across the southern hemisphere late last month as it passed its perihelion (the closest point to the sun).
Now, it's heading toward Earth and just starting to appear in northern skies around dawn, though it's still very close to the horizon.
If you're hoping for a better view, the comet will rise higher in the sky over the next week or two, making the best viewing time after dusk in mid-October — and lucky for us, EarthSky reports it's only getting brighter.
In fact, according to the Farmers' Almanac, there's a chance Comet A3 could become bright enough to outshine Venus in the sky for a short time in October, making it visible during the day thanks to a phenomenon called forward-scattering. However, comets are notoriously hard to predict, and there's still a chance it won't be quite that bright.
That said, this comet takes around 80,000 years to orbit the sun, according to NASA — so assuming it's visible, this will still be a once-in-a-lifetime sight.
Here's everything you need to know about when and how to get the best view of Comet Tsuchinshan-ATLAS from Canada.
How bright will Comet A3 be?
This comet has the potential to become one of the brightest comets we've seen in recent years, with the Farmers' Almanac reporting that it might even outshine the brightest stars in the sky and be visible during daylight for a brief period.
This brightness is expected due to forward-scattering, a phenomenon where sunlight reflects off the particles in the comet's tail and is directed toward Earth. If this happens, the comet could reach a brightness of magnitude -5, making it brighter than Venus.
Still, NASA and other astronomers caution that comets are unpredictable, so we won't know for sure until it arrives.
How close will it get to Earth?
According to NASA, Comet Tsuchinshan-ATLAS will come within 70 million kilometres of Earth at its closest point on October 12, 2024.
To put that into perspective, the moon orbits the Earth at a distance of about 384,400 kilometres, while Venus can come as close as 40 million kilometres at its closest point.
So while there's no threat of the comet plummeting toward Earth, it's still relatively close by space standards, giving us a fantastic opportunity to see it.
When will Comet A3 be visible?
While the best chance to spot Comet Tsuchinshan-ATLAS will be around October 12, when it's closest to Earth, you'll actually have a decently large window to catch a glimpse.
The comet is already beginning to be visible in the morning sky just before sunrise. However, starting around October 13 or 14, it should become easier to see in the evening sky, according to EarthSky, climbing even higher in the sky over the subsequent days.
If we're lucky, the comet will continue to be visible through late October in the northern hemisphere, though it will start to dim as it moves away from the sun (and us).
Where and how can you find it?
To catch a glimpse of Comet Tsuchinshan-ATLAS, look toward the southwest sky after sunset. The comet will be higher in the sky as the days go on, making it easier to spot.
As with any stargazing, for the best view, it's a good idea to head away from city lights as light pollution can make it much harder to see faint celestial objects. Find a dark, open area with a clear view of the horizon to maximize your chances of seeing the comet's glowing tail.
You can also download a stargazing app like Night Sky, which can help you find celestial objects in the night sky wherever you are in real time.
Do you need a telescope to see Comet A3?
You might not! Comet Tsuchinshan-ATLAS is predicted to be bright enough to see with the naked eye, but for the best view, a pair of binoculars or a small telescope could help, especially as it begins to fade around the end of the month.
Happy stargazing, Canada!
This article's cover image was used for illustrative purposes only.
Love this? Check out our MTL Blog noticeboard for details on jobs, benefits, travel info and more!
AI tools may have been used to support the creation or distribution of this content; however, it has been carefully edited and fact-checked by a member of MTL Blog's Editorial team. For more information on our use of AI, please visit our Editorial Standards page.
