After months of speculation about whether comet A3 — also known as comet Tsuchinshan-ATLAS and C/2023 A3 — would become visible to the naked eye when it approached the sun in late September, the first images are in. It’s looking good.
“Set your alarm for dawn. Comet Tsuchinshan-ATLAS is so bright, people are seeing it in the twilight glow of sunrise,” states SpaceWeather.com in an email to its subscribers.
Comet A3 Time-Lapse Video From Space
The picks of the new images of comet A3 come from two NASA astronauts on the International Space Station, Matthew Dominick and Don Pettit, who have both published a time-lapse and images of comet A3 visible from orbit to X. “So far Comet Tsuchinshan-ATLAS looks like a fuzzy star to the naked eye looking out the cupola windows,” wrote Dominick on X. “But with a 200mm, f2 lens at 1/8s exposure, you can really start to see it. This comet is going to make for some really cool images as it gets closer to the sun.”
Comet A3 Photos From Space
“It is totally awesome to see a comet from orbit, ” wrote Pettit on X. “The perspective of rising through the atmosphere on edge is truly unique from our vantage point. The comet tail is still too dim to see with your eyes, but it is heading towards the sun and growing brighter every day.” Petitt — who shot the comet using a Nikon Z9 camera with a 20mm lens — added that he intends to photograph the comet every day to see how the structure of the comet’s tail changes.
Why Comet A3 Has Tails
As a comet gets closer to the sun, it heats up slightly. That causes the ice covering its nucleus to become a gas, creating a coma. This gas — and dust — from the coma trails behind the comet, causing a tail that can be hundreds of millions of miles long. As of late-Sept., its tail is about 27 degrees in length, according to The Sky Live.
Comet A3 — as with many comets — actually has two tails. Its plasma tail is made of ionized gas, while its dust tail is made of dust. It’s visible to us because the comet ismoving towards being between the sun and the Earth, so its tail reflects sunlight more than most comet tails. It is known as “forward scattering” to astronomers because it scatters sunlight in the direction of Earth — and into your eyes — and the phenomenen is expected to increase over the next few weeks.
When And Where To See Comet A3
Comet A3 will get closest to the sun on Sept. 27 in the morning sky and, once it drifts northwards into the evening sky, closest to Earth on Oct. 12.
“You can use the Moon to find Comet A3 Tsuchinshan-ATLAS in the sky before sunrise later this week,” wrote amateur astronomer Stuart Atkinson on X, referring to Sept. 28, 29 and 30. “The comet will look like a fuzzy star with a misty tail beneath the Moon, very low in the east. You might need binoculars to see it.”
Wishing you clear skies and wide eyes.
