Luminous Fast Blue Optical Transients (LFBOTs)

[Astronuc]

Among the more puzzling cosmic phenomena discovered over the past few decades are brief and very bright flashes of blue and ultraviolet light that gradually fade away, leaving behind faint X-ray and radio emissions. With slightly more than a dozen discovered so far, astronomers have debated whether they are produced by an unusual type of supernova or by interstellar gas falling into a black hole.

Analysis of the brightest such burst to date, discovered last year, shows that they’re neither.

Instead, a team of astronomers led by researchers from the University of California, Berkeley, concluded that these so-called luminous fast blue optical transients (LFBOTs) are caused by an extreme tidal disruption, where a black hole of up to 100 times the mass of our sun completely shreds its massive star companion within days.

The discovery resolves a decade-long conundrum but also illustrates the many varieties of stellar calamities that astronomers encounter, each with its characteristic spectrum of light — different wavelengths, different intensities — that evolves over time. Figuring out the processes that produce these unique light signatures tests current knowledge of the physics of black holes and helps astronomers understand the evolution of stars in our universe.

UC Berkely, December 16, 2025
https://news.berkeley.edu/2025/12/1...-blue-cosmic-flashes-astronomers-find-a-clue/

AT 2024wpp, a luminous fast blue optical transient, or LFBOT, is the bright blue spot at the upper right edge of its host galaxy, which is 1.1 billion light-years from Earth in (or near) a galaxy far, far away.

LFBOTs got their name because they are bright — they’re visible over distances of hundreds of millions to billions of light-years — and last for only a few days, producing high-energy light ranging from the blue end of the optical spectrum through ultraviolet and X-ray. The first was seen in 2014, but the first with sufficient data to analyze was recorded in 2018 and, per the standard naming convention, was called AT 2018cow. The name led researchers to refer to it as the Cow, and subsequent LFBOTs have been called, tongue in cheek, the Koala (ZTF18abvkwla), the Tasmanian Devil (AT2022tsd) and the Finch (AT2023fhn).

Such objects are very bright (obiously) and very energetic. The article indicates that AT 2024wpp had a peak luminosity of 2-4 x 10⁴⁵ erg/s, and radiated >10⁵¹ ergs over 45 days. For comparison, the Sun's radiant power (luminosity) is on the order of 3.8-3.9 x 10³³ ergs/s. (Ref: https://www.ucolick.org/~bolte/AY4_00/week4/star_lum.html , https://en.wikipedia.org/wiki/Luminosity)

Like most LFBOTs, AT 2024wpp is located in a galaxy with active star formation, so large, young stars like these are expected. AT 2024wpp is 1.1 billion light-years away and between five and 10 times more luminous than AT 2018cow.

Astronomers Pinpoint Black Holes as the Power Source Behind Mysterious Cosmic Flashes
https://keckobservatory.org/at2024wpp/

ALMA Helps Unmask Monster Black Hole Behind Record-Breaking Cosmic Burst
https://public.nrao.edu/news/alma-h...ack-hole-behind-record-breaking-cosmic-burst/

The Most Luminous Known Fast Blue Optical Transient AT 2024wpp: Unprecedented Evolution and Properties in the Ultraviolet to the Near-Infrared - https://arxiv.org/abs/2509.00951

Investigating the Most Luminous Known Fast Blue Optical Transient
https://aasnova.org/2025/12/05/investigating-fast-blue-optical-transient-at2024wpp/


An article from Space.com on Yahoo had caught my attention, so I had to go to other sources.
https://www.yahoo.com/news/articles/mysterious-bright-blue-cosmic-blasts-220000349.html