Artist’s Concept of Luminous Fast Blue Optical Transient

This is an artist’s concept of one of the brightest explosions ever seen in space. Called a Luminous Fast Blue Optical Transient (LFBOT), it shines intensely in blue light and evolves rapidly, reaching peak brightness and fading again in a matter of days, unlike supernovae which take weeks or months to dim. Only a handful of previous LFBOTs have been discovered since 2018. And they all happen inside galaxies where stars are being born. But as this illustration shows, the LFBOT flash discovered in 2023 by Hubble was seen between galaxies. This only compounds the mystery of what these transient events are. Because astronomers don’t know the underlying process behind LFBOTs, the explosion shown here is purely conjecture based on some known transient phenomenon.

[Image Description: An illustration of one of brightest explosions ever seen in space. Called a Luminous Fast Blue Optical Transient (LBOT), it shines intensely in blue light. It appears as a bright white blob left of centre where blue-white and red rays sprout out from it. Toward the right of the image there is a white spiral galaxy. To the upper left is another whitish galaxy shaped like a cigar. The LFBOT doesn’t seem to be associated with either galaxy.]