An extraordinarily bright explosion detected by NASA’s Hubble Space Telescope has left scientists perplexed. The bright flash of blue light appeared in the middle of empty space and is believed to have burned at 36,000 degrees Fahrenheit. This rare explosion, known as a ‘Luminous Fast Blue Optical Transient (LFBOT),’ is one of the brightest and most unpredictable visible-light events in the universe.
“The discovery poses many more questions than it answers,” said NASA Hubble on X (formerly Twitter). An LFBOT is an intense burst of blue light that evolves rapidly. While Hubble was able to pinpoint the location of one, astronomers are confounded by its appearance far between two galaxies, away from any host galaxy. Previous LFBOTs have been found in star-forming regions within galaxies’ spiral arms, so the cause for this occurrence is still uncertain.
These cosmic explosions, also known as LFBOTs, were first discovered in 2018, and only a few have been found since then. Scientists have proposed various explanations for their origins, though they remain poorly understood. Currently, LFBOTs are detected once per year.
The latest LFBOT, nicknamed ‘Finch,’ was detected by the Zwicky Transient Facility on April 10, 2023. It appeared in an unexpected location, far from any host galaxy. NASA’s Hubble Space Telescope was able to pinpoint its precise location, approximately 50,000 light years from a nearby spiral galaxy and 15,000 light years from a smaller galaxy.
“It shined intensely in blue light and evolved rapidly, reaching peak brightness and fading in a matter of days, unlike supernovae, which take weeks or months to dim,” explained NASA. Additionally, Hubble’s observations revealed that Finch is situated between two neighboring galaxies, setting it apart from previous LFBOTs.
Various hypotheses have been presented to explain the cause of these bright blue flashes. One possibility is that they are a rare type of supernova known as core-collapse supernovae. However, the fact that Finch was found in intergalactic space challenges this theory, as supernovae are typically found in the spiral arms of galaxies where star birth occurs. Further investigation is needed to determine the true origin of LFBOTs.
“The discovery poses many more questions than it answers,” said Ashley Chrimes, a European Space Agency research fellow. “More work is needed to figure out which of the many possible explanations is the right one,” he added.