The ATLAS survey in Hawaii discovered a new sungrazing comet on September 27, 2024, which is part of the Kreutz sungrazing family and is expected to reach its perihelion on October 28, 2024. The comet is yet to be officially named and has been provisionally designated as A11bP71.
A sungrazing comet from the Kreutz family refers to a group of comets that pass extremely close to the Sun at their perihelion. The comets from this family formed over 1 000 years ago after a giant comet broke up. The perihelion is the point in an object’s orbit where it is closest to the sun.
Comet A11bP71 could reach a brightness of magnitude -5 to -7 at perihelion, making it brighter than Venus, the brightest planet in the sky.
In astronomical terms, a lower magnitude indicates greater brightness. Some bright stars have a magnitude of around 1 or 2, while planets like Venus can have negative magnitudes, making them visible even during the daytime.
Normally several objects from the Kreutz family pass by the Sun every day and disintegrate as they are generally quite small but A11bp71 could survive the perihelion and become visible to the naked eye as it is a larger fragment than the rest.
The comet will be visible in the southern hemisphere before reaching perihelion, while the northern hemisphere will have the best view after it passes by the Sun, provided it survives the close encounter.
“The orbit and brightness of A11bP7I remind experts of Comet Lovejoy (C/2011 W3), a sungrazer that flew through the Sun’s atmosphere in December 2011,” Dr. Tony Phillips of SpaceWeather.com reports.
Comet Lovejoy emerged from the close encounter intact and put on a spectacular show for amateur astronomers during the Christmas holidays of that year.
Experts have also pointed out similarities between the orbits of the newly identified object A11bP7I and the Great Comet Ikeya-Seki (C/1965 S1). Ikeya-Seki, which became a prominent sight in 1965, was also a member of the Kreutz group of sungrazing comets.
When Ikeya-Seki passed perihelion (its closest approach to the Sun), it reached an extraordinary brightness, with an estimated magnitude of -10. This level of brightness made it one of the brightest comets observed in the 20th century.
Observers in Japan were able to see Ikeya-Seki even in daylight, with some reports mentioning visibility at high noon. The comet’s tail extended for several degrees across the sky, making it a spectacular sight for those who witnessed it. The comparison between A11bP7I and Ikeya-Seki is based on orbital patterns that suggest both objects could share similar trajectories around the Sun, though more data would be required to confirm if A11bP7I could achieve a similar level of brightness or prominence.
The potential for A11bP7I to exhibit similar characteristics to Ikeya-Seki has sparked interest in the astronomical community, but it remains uncertain whether it will produce the same dramatic visual effects as Ikeya-Seki. Much will depend on the object’s size, composition, and the specific conditions it encounters as it nears the Sun.
Dr. Karl Battams, a sungrazing comet expert and Principal Investigator of NASA’s Sungrazer Project, expressed a mix of optimism and caution regarding the comparison between A11bP7I and the Great Comet Ikeya-Seki.
While he hopes for the possibility of an “Ikeya-Seki 2.0,” he also suggested that the object could simply be a smaller Kreutz fragment that has shown activity earlier than expected.
Battams urged caution in drawing direct parallels to Ikeya-Seki, although he acknowledged that a scenario similar to that of Comet Lovejoy might still be possible.
References:
1 What’s up in space – Spaceweather.com– September 30, 2024