Bright blue flashes are coming to Earth from deep space – but what are they?
Usa today news
Something out in space is sending us very bright blasts of blue light – and now researchers may have figured out what they are. The phenomenon is known as luminous fast blue optical transients (or LFBOTs) and comes in the form of short, bright flashes of light that fade away and leave behind X-ray and radio emissions. They have puzzled researchers for over a decade, despite scientists having spotted more than a dozen of them. (Picture: Getty)
Attempts by experts to to explain them have spanned everything from strange supernovae to interstellar gas being eaten by a black hole. But now scientists believe they have another cause. After studying a new example, which was found last year and was the brightest of its kind, the researchers say that the LFBOTs are caused by ‘extreme tidal disruption’. That happens when vast black holes eats its companion star, tearing it to shreds. (Picture: Getty)
Discovering this means that as well as helping explain the mysterious phenomenon, the research could help us better understand how black holes work and the ways that stars evolve. For example, scientists still don’t know how huge black holes actually come to form. (Picture: Getty)
Senior author Dr Raffaella Margutti said: ‘Theorists have come up with many ways to explain how we get these large black holes, to explain what LIGO (Laser Interferometer Gravitational-Wave Observatory) sees LFBOTs allow you to get at this question from a completely different angle. They also allow us to characterize the precise location where these things are inside their host galaxy, which adds more context in trying to understand how we end up with this setup — a very large black hole and a companion.’(Picture: Getty)
LFBOTs got their name because they are bright and visible over distances of hundreds of millions to billions of light-years, but they only last a few days, producing high-energy light ranging from the blue end of the optical spectrum through ultraviolet and X-ray. The first one was seen in 2014, but the first with sufficient data was analysed in 2018, and was called AT 2018cow. (Picture: Getty)
The newest LFBOT is named AT 2024wpp and was analysed in two papers recently accepted by The Astrophysical Journal Letters. The researchers realised that the transient outburst could not have resulted from a supernova after the researchers calculated the energy emitted. It turned out to be 100 times greater than what would be produced in a normal supernova, which would require the conversion of about 10% of the rest mass of the sun into energy over a very short time scale, mere weeks.(Picture: Getty)
First author of one of the papers, Natalie LeBaron, said: ‘The sheer amount of radiated energy from these bursts is so large that you can’t power them with the collapse and explosion of a massive star – or any other type of normal stellar explosion. The main message from AT 2024wpp is that the model that we started off with is wrong. It’s definitely not caused by an exploding star.’ (Picture: Getty) Add Metro as a Preferred Source on Google Add as preferred source
