Is the comet still visible? Yes, but only if you use binoculars and wait a couple of hours after sunset. Comet Tsuchinshan-ATLAS — also called comet A3 and C/2023 A3 – is no longer a naked-eye object, it’s visible this week in a dark, moonless night sky.
That makes it possible to see it with the Milky Way, which is just visible in the west after sunset if you’re in a dark sky destination. The comet is in the constellation Ophiuchus, close to the famous three bright stars of the famous “Summer Triangle” asterism, where the Milky Way currently flows through to the horizon.
If you’re lucky, the spike in solar activity this week will translate to Northern Lights at lower latitudes, too, giving a potentially rare double-act of cosmic views.
Where Is Comet Tsuchinshan-ATLAS?
Now 94 million miles (151 million kilometers) from Earth and shining at a magnitude of +4.3 in the constellation Ophiuchus, the comet is now getting fainter and smaller with each passing night.
A pair of binoculars or a small telescope will get you a view. Another way to see it is to 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.
How To Locate Comet Tsuchinshan-ATLAS: Friday, Nov. 1
Position: west, 56 degrees from the sun in Ophiuchus
Time: from 60 minutes after sunset where you are until about 22:30 local time
Magnitude: +4.3
Comet’s distance from the sun: 88 million miles (141 million kilometers)
Comet’s distance from Earth: 94 million miles (151 million kilometers)
How To Find The Comet Using Venus
If you look southwest about an hour after sunset, you’ll likely see the bright planet Venus. That’s your guiding light to the comet.
Look above Venus for the bright star Vega in the constellation Lyra. Look halfway between Venus and Vega, and you should find the comet, though probably only if you use a pair of binoculars.
How To Find The Comet Using The Summer Triangle
Since Venus will sink soon after sunset — or you may have horizon clouds or mountains to contend with — you can also use the stars of the Summer Triangle, of which Vega is one. Find the other two that make up the famous asterism — Deneb in Cygnus, above Vega, and Altair in Aquila, to the left.
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. You’ll need binoculars to see it — as well as a dark, clear sky.
What Is Comet Tsuchinshan-ATLAS?
It’s a long-period comet from the Oort Cloud, a sphere around the solar system that’s home to millions of comets. Astronomers think it loops around the sun once every 80,000 years. 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.
Check my feed for a daily “comet tracker,” with useful sky charts and tips for viewing the comet.
Wishing you clear skies and wide eyes.
