The brightest cosmic event ever seen might have shed light on mysterious blue explosions in space. This discovery centers around a signal from a Luminous Fast Blue Optical Transient (LFBOT) called AT 2024wpp. First identified in 2024, this signal led scientists to understand that LFBOTs are linked to extreme Tidal Disruption Events (TDEs). These events occur when a black hole, up to 100 times the mass of our sun, tears apart a companion star in just days.
So far, only about a dozen LFBOTs have been spotted, puzzling astronomers for nearly a decade. Initial theories included rare exploding stars known as supernovas or interstellar gas being consumed by black holes. However, AT 2024wpp’s energy output was found to be about 100 times more than average supernovae, helping to eliminate these earlier hypotheses.
When astronomers took a closer look at AT 2024wpp, they noted an unusual excess of near-infrared light, a characteristic shared with the earlier LFBOT, AT 2018cow. This newly found LFBOT, standing out for its brightness, doesn’t yet have a catchy nickname like its predecessors “The Cow,” “The Koala,” or “The Tasmanian Devil.” But enthusiasts are eager to see what name it will receive.
Research showed that the amount of energy released by these events surpasses what typical stellar explosions can produce. As noted by Natalie LeBaron from the University of California, Berkeley, “The amount of energy radiated is so large that it can’t be powered by any ordinary star explosion.” This insight shifts our understanding of these cosmic phenomena significantly.
Tidal Disruption Events happen when a star gets too close to a black hole and gets “spaghettified,” creating a trail of stellar material. Not every TDE results in a bright LFBOT, which raises the question: What’s different about the LFBOT-inducing TDEs? One theory suggests that in the case of AT 2024wpp, the black hole had been feeding off a companion star for an extended period. When the star finally ventured too close, it created a burst of light and energy seen from billions of light-years away.
Recent research estimates that the shredded star had a mass around ten times that of the sun and was likely a Wolf-Rayet star—an evolved star nearing the end of its life. These stars tend to emit weak hydrogen radiation and are somewhat common in actively star-forming galaxies.
This discovery is not only groundbreaking but incredible to think that we can observe such massive cosmic events from so far away. The findings from team members have recently been accepted for publication in The Astrophysical Journal Letters and are also available for review on arXiv.
