On April 10, the Zwicky Transient Facility at Palomar Observatory in California detected an LFBOT designated AT2023fhn but nicknamed “The Finch,” following an eclectic naming pattern scientists have adopted for the confusing phenomena.
LFBOTs are kind of like supernovas or gamma ray bursts, but they’re much brighter than supernovae and they shine in bright blue light and also emit a lot of radio waves, ultraviolet rays, and x-rays, but not much else. They also only last for a few days, whereas supernovae typically last for weeks or months.
During the brief time The Finch stuck around, it was also observed by the Gemini South telescope in Chile, the Very Large Array radio telescope, and the Hubble Space Telescope and Chandra X-ray Observatory in Earth orbit.
Gemini was able to tell through spectral analysis that The Finch was about 20,000 degrees Celsius, well short of a supernova or even of a massive star but much hotter than our sun, for example. The light’s red-shift showed it occurred about 3 billion light-years away, which is why the Hubble’s massive eye was called on to check it out.
Ashley Chrimes, a research fellow at the European Space Agency, is the lead author of a new paper describing the mystery, which was accepted for publication in the Monthly Notices of the Royal Astronomical Society journal and released on the preprint server arXiv.
"The more we learn about LFBOTs, the more they surprise us," Chrimes said in a statement. "We've shown that LFBOTs can occur a long way from the center of the nearest galaxy, and the location of the Finch is not what we expect for any kind of supernova."
“The discovery poses many more questions than it answers,” Chrimes added. “More work is needed to figure out which of the many possible explanations is the right one.”
Some theories floated in the news release are that LFBOTs could be the result of stars being torn apart by intermediate-mass black holes, or could be the result of a collision between two neutron stars in which one of them was a magnetar.
Officials noted the James Webb Space Telescope (JSWT), another space-based observatory with a far more powerful lens than the Hubble, could be used to look at The Finch’s location with much greater scrutiny. The scientists stated that JWST might find it occurred in a globular cluster in the outer halo of one of the nearby galaxies, which is the most likely place to find intermediate-mass black holes, too.