The distant star appears to have come back to life after its explosive death, exploding in repeated bursts of energy over months that astronomers have never seen before. Although each flare lasts only a few minutes, even 100 days after the initial burst, they all remain as bright and powerful as the original burst; A rare type of starburst called “fast bright blue optical transient” or LFBOT. This particular LFBOT is about a billion light-years away from Earth and is officially named AT2022tsd and nicknamed the “Tasmanian Devil” by its discoverers.

Far brighter than the usual explosions that mark the death of massive stars, LFBOTs fade more quickly after death, within days rather than weeks. These extreme phenomena were first discovered in 2018, and in the fifteen years since then their origins have become shrouded in mystery. But an unprecedented outbreak of Tasmanian devil activity may provide some answers. This behavior, observed by 15 different telescopes around the world, suggests that the engine driving LFBOTS is either a black hole or a neutron star (the remnants left behind when truly massive stars die).

“We don’t think anything else could cause such outbreaks,” Anna IK said. Ho is the study’s lead author and an associate professor of astronomy at Cornell University. “This ends the long-standing debate about what the power of this type of explosion is and paves the way for a fairly direct method of studying the activity of stellar bodies.”

A new kind of cosmic disaster

The Tasmanian devil was first identified using software developed by Ho in September 2022, when the system looked at data containing about half a million variable objects. or transients detected with the Zwicky Transient Facility.

Later, during regular monitoring of LFBOT as it faded in December 2022, Ho and colleagues detected another burst of bright light coming from the event. The spike then immediately disappeared.

“Nobody actually knew what to say. Ho, we’ve never seen anything like this in any supernova or FBOT before; anything as fast and bright as the first explosion a few months later. “We’ve never seen it. and period in astronomy.”

To investigate this unexpected “return to life” of the Tasmanian devil, the team collected observations from 12 other telescopes, including one that recorded the event with a high-speed camera. After eliminating other possible light sources, the researchers were left with 14 irregular pulses of light that occurred over 120 days. Ho believes this may have been just a fraction of the total number of flares in the entire incident.

“Surprisingly, instead of constantly coming out as you would expect, the source lit up again and again for short periods of time,” he said. “LFBOT is already a strange, exotic event, so this was even stranger.”

Now Ho and his colleagues plan to investigate the processes that cause these bursts of light. The current prime suspects are jets of matter that are driven by the black hole’s magnetic field and explode at the speed of light. However, the possibility of LFBOTs emerging from black hole collisions and mergers remains.

“We may be observing a completely different channel for cosmic catastrophes,” Ho said.

The research could ultimately help learn more about how stars die and the types of stellar debris they leave behind. Essentially, LFBOTs could provide the ability to observe stars transitioning from ‘life’ to ‘death’. Source