On September 28, astronauts aboard the International Space Station captured an incredible image of Comet C/2023 A3 (Zijinsan-Atlas). As the end of October approaches, astronomy enthusiasts are in for a rare cosmic treat as this comet becomes visible in the northern hemisphere’s night sky. It will appear shortly after sunset in the low western sky, enabling viewers to witness this unusual celestial event with the naked eye. With an orbital period of over ten thousand years, this comet won’t be seen again for many millennia, prompting stargazers in the San Francisco Bay Area to prepare for the best possible viewing opportunities.

According to NASA, Comet C/2023 A3 was discovered in 2023 by a collaboration between the Zijinsan Observatory in Nanjing, China, and the ATLAS asteroid observation system. This ancient and mysterious comet is believed to originate from the Oort Cloud, a vast region surrounding our solar system filled with interstellar debris and celestial bodies. The Oort Cloud is distant and contains billions of frozen objects, with many comet-like bodies having incredibly long orbital periods that rarely bring them close to Earth – often spanning thousands to even tens of thousands of years. This particular comet takes approximately 60,000 to 80,000 years to complete one orbit around the Sun, making it one of the most anticipated comets of 2024.

Starting from October 12, Comet C/2023 A3 has emerged as an evening star in the northern hemisphere, positioned very low in the western sky near the Virgo constellation shortly after sunset. Its brightness peaked at negative magnitudes, providing an optimal moment for observation. Many astronomy enthusiasts in the San Francisco Bay Area have already reported sighting the comet streaking across the sky, with some able to capture images using just their smartphones.

From October 13 to 14, although the comet’s brightness gradually declined to magnitude 0 to 1, observing it became somewhat easier due to its distance from the Sun. On October 15, the comet will pass very close to the M5 globular cluster, offering photographers an exceptional opportunity for stunning captures. It’s also possible to witness a phenomenon known as anti-tail, where a bright streak points toward the Sun, opposite the direction of the traditional comet tail.

Scientists suggest that, over time, the comet’s brightness will continue to diminish. From October 20 to 31, its magnitude is predicted to drop from 4.5 to 7, at which point the tail will become noticeably longer. For skywatchers eager to spot this beautiful celestial body, finding an open location away from city lights after sunset will enhance their chances of successful observation. NASA recommends using binoculars or small telescopes for the best experience. For those looking to capture clearer images of the comet, utilizing a camera’s long exposure feature can yield better results.