Can you still see the comet this weekend? Yes — and, thanks to yesterday’s New Moon, you can see it in a dark sky — but you will need a pair of binoculars or a small telescope.
Comet Tsuchinshan-ATLAS — also called comet A3 and C/2023 A3 – is no longer a naked-eye object, but it’s now visible in a dark, moonless night sky for a few hours after sunset. As a bonus, you’ll also have a chance to see some ultra-bright “Halloween fireballs” shooting stars from the South Taurid meteor shower, which peaks this week.
Now in the constellation Ophiuchus, the comet can be found just below the iconic “Summer Triangle” asterism, which comprises three bright stars across the Milky Way.
Comet Tracker: Where Is Comet Tsuchinshan-ATLAS?
Now 97 million miles (156 million kilometers) from Earth and shining at a magnitude of +6, the comet is now getting fainter and smaller with each passing night.
If you don’t have a pair of binoculars or a small telescope, photograph the comet with a camera or a smartphone, with a long exposure image of a few seconds showing it more easily.
Note: times and viewing instructions are for observers at mid-latitudes in the Northern Hemisphere. Check the exact time of sunset where you are and the comet’s setting times on Stellarium Web for times that are accurate for your exact location.
Comet Tracker: Where Is Comet Tsuchinshan-ATLAS On Nov. 2-3?
Position: west, 56 degrees from the sun in Ophiuchus
Time: from 60 minutes after sunset where you until about 22:30 local time
Magnitude: +6
Comet’s distance from the sun: 89 million miles (144 million kilometers)
Comet’s distance from Earth: 97 million miles (156 million kilometers)
Comet Tracker: How To Find The Comet Using Venus
Look to the southwest about an hour after sunset and you’ll see the bright planet Venus shining close to the horizon. Above the planet will be bright star Vega in the constellation Lyra. One of the brightest, most famous and most important stars in the night sky, astronomers this week found no evidence of giant planets around Vega.
Look halfway between Venus and Vega, and you should find Comet Tsuchinshan-ATLAS in binoculars.
Comet Tracker: How To Find The Comet Using The Summer Triangle
Venus will sink soon after sunset, and in any case is more difficult to see from northern latitudes, so here’s another way to find the comet using the stars of the Summer Triangle, of which Vega is one. Find Deneb in Cygnus, above Vega, and Altair in Aquila, to the left. That’s the Summer Triangle.
Now, make a rough triangle between Altair and Vega by pointing down to the horizon. The third point is roughly where the comet will be.
Comet Tracker: What Is Comet Tsuchinshan-ATLAS?
Comet Tsuchinshan-ATLAS is a long-period comet from the Oort Cloud, a sphere around the solar system that’s home to millions of comets. Its coma is about 130,000 miles (209,000 kilometers) in diameter, and its tail extends around 18 million miles (29 million kilometers) into space. It has an orbital period of 80,000 years.
Check my feed for “comet tracker” articles, each with useful sky charts and tips for viewing the comet.
Wishing you clear skies and wide eyes.