A newly discovered comet, C/2023 A3 Tsuchinshan–ATLAS, is set to make a spectacular appearance in the night sky this Saturday, marking a rare celestial event that enthusiasts won’t want to miss. This may be the last opportunity to observe this ancient comet for an astonishing 80,000 years, when it is expected to return to our solar system.
The Journey of Tsuchinshan–ATLAS
The comet achieved perihelion—the closest point to the sun—in its orbital path on September 27, 2024. During this period, it was visible primarily to observers in the Southern Hemisphere. However, as it continues its trajectory out of the inner solar system, it will become increasingly visible to those in the Northern Hemisphere from mid-October through early November, according to NASA.
On Saturday, C/2023 A3 Tsuchinshan–ATLAS will approach Earth at a distance of approximately 44 million miles (nearly 71 million kilometers). This flyby marks the comet’s first documented encounter with our planet, and with its 80,000-year orbit, it would have last been seen during the era of the Neanderthals.
Viewing the Comet
For those eager to catch a glimpse of this once-in-a-lifetime event, the best viewing opportunity will be in the western night sky shortly after sunset. According to EarthSky, the comet will appear as a bright fireball adorned with a long, trailing tail. Bill Cooke, the lead of NASA’s Meteoroid Environment Office at the Marshall Space Flight Center, recommends using binoculars for an enhanced viewing experience.
“It won’t streak across the sky like a meteor; instead, it will seem to hang there and slowly change position from night to night,” Cooke explained. “If you manage to see the comet with your naked eye, using binoculars will be an awe-inspiring experience.”
The Discovery of Tsuchinshan–ATLAS
The comet was independently discovered in 2023 by astronomers using China’s Tsuchinshan Observatory and the Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in South Africa, leading to its unique name. Tsuchinshan–ATLAS originates from the Oort Cloud, a vast, mostly spherical region containing comets that are loosely bound to our solar system, located thousands of times farther from the Sun than our planet.
Scientists initially speculated whether the comet—composed of ice, frozen gases, and rocky materials—would survive its passage around the sun. Fortunately, the comet appears largely intact, with Cooke stating, “It made it through with flying colors.”
Brightness and Visibility
Due to its close proximity to the sun, Tsuchinshan–ATLAS will experience a phenomenon known as forward scattering, causing it to reach its peak brightness around Wednesday. However, the sun’s glare may hinder visibility until a few days later. If all goes well, the comet will return to this point in its orbit in about 80,000 years; however, comets are unpredictable, and gravitational forces from other planets could alter its path.
For those unable to witness Tsuchinshan–ATLAS in person, the Virtual Telescope Project in Italy will offer a live feed of the comet during its brightest moment on Wednesday and again on Saturday during its closest approach to Earth.
A Memorable Experience
Seeing a bright comet in the night sky is often described as a transformative experience, especially for children. Dr. Teddy Kareta, a postdoctoral associate at Lowell Observatory, emphasized the rarity of such celestial events. “Even though there are comets every couple of years, those that are easily visible are few and far between,” Kareta stated. “If you can catch a glimpse of Tsuchinshan–ATLAS, do so, and take others with you to share in the experience.”
Upcoming Celestial Events
Sky-watchers should be aware that the upcoming full moon, peaking on October 17, might interfere with comet visibility due to its illumination, making it the hunter’s moon and the closest supermoon of the year, at 222,095 miles (357,428 kilometers) from Earth.
Additionally, enthusiasts can look forward to another comet, C/2024 S1 (ATLAS), which may make its appearance in the night sky later in October, providing even more opportunities to explore the wonders of the universe.
The appearance of C/2023 A3 Tsuchinshan–ATLAS offers a unique chance to witness a celestial marvel that may not be seen again for thousands of years. As the comet approaches Earth, prepare your binoculars and gather friends and family for a memorable night of stargazing. Don’t miss out on this extraordinary cosmic event!