Astronomers have spotted something truly exciting: an enormous star might have exploded while interacting with a black hole. This discovery could introduce a new category of stellar explosions.
The event, called SN 2023zkd, was first noticed in July 2023 by the Zwicky Transient Facility in California. Situated about 730 million light-years away, it was identified using a new artificial intelligence (AI) system designed to flag unusual cosmic happenings. This early detection allowed researchers to observe the explosion from its very beginnings.
Astronomer Ashley Villar from Harvard University remarked, “SN 2023zkd shows some of the clearest signs we’ve seen of a massive star interacting with a companion before it exploded. We think this may lead to discovering a new class of hidden explosions.”
Initially, it looked like a standard supernova, a bright flash marking the death of a star. However, as time passed, astronomers noticed it getting brighter again. They reviewed older data and found that the brightness had been increasing for about four years, suggesting the star was under significant gravitational strain.
The likely scenario is that the star was in orbit around a black hole. Light curves and spectral data indicate that the star experienced two major eruptions before its demise, releasing vast amounts of gas. The first peak of light came when the explosion wave struck low-density material, while the second peak appeared months later from a slow collision with a dense cloud. Over time, the black hole’s gravity might have destabilized the star, leading to its collapse.
In another theory, the black hole could have destroyed the star before it had a chance to explode naturally. In this case, the debris from the destruction would emit the supernova’s light while crashing into surrounding gas. Regardless of how it happened, the end result would lead to the formation of a larger black hole.
Alexander Gagliano, the study’s lead author, stated that “SN 2023zkd provides strong evidence that close interactions can detonate a star.” He noted that while many massive stars are in binary systems, witnessing one actively exchanging mass before its explosion is incredibly rare.
The findings showcase the power of AI in identifying rare cosmic events just in time for detailed study. The Vera C. Rubin Observatory, set to start operations soon, is expected to revolutionize our understanding of these extraordinary occurrences by documenting the entire southern sky every few nights.
With this combination of real-time AI detection and the Rubin Observatory’s capabilities, astronomers will be able to observe and study even more of these unique events. As Gagliano put it, “We’re entering an era where we can catch these rare events as they happen, allowing us to connect the dots between how stars live and die, and that’s incredibly exciting.”
This groundbreaking research was detailed in a paper published in the Astrophysical Journal on August 13. As we advance in technology, the cosmos will continue to reveal its secrets, shedding light on the life cycles of massive stars and their interactions with black holes. For further reading on cosmic phenomena, visit the NASA website for insights into ongoing space explorations and discoveries.
