The star will appear in the constellation Cygnus, also know as the Northern Cross. Photo / 123rf
At the beginning of the 3rd century civil war raged in Britain as the Roman emperor Septimius Severus sought to quell unrest in the north.
But unknown to the fighting cohorts and Caledonian tribes, high above their heads two stars were coming together in a huge cataclysmic explosion.
Now 1800 years later the light from that collision will finally arrive on Earth creating a new star in the night sky - dubbed the 'Boom Star - in an incredibly rare event which is usually only spotted through telescopes.
Before their meeting the two stars were too dim to be seen by the naked eye, but in 2022, the newly formed Red Nova will burn so brightly in the constellation Cygnus that everyone will be able to to see it.
"For the first time in history, parents will be able to point to a dark spot in the sky and say, 'Watch, kids, there's a star hiding in there, but soon it's going to light up," said Dr Matt Walhout, dean for research and scholarship at Calvin College, Michigan, where the prediction was made.
For around six months the Boom Star will be one of the brightest in the sky before gradually dimming, returning to its normal brightness after around two to three years.
It is the first time scientists have ever predicted the birth of a new star and astronomers in Britain said it would be a fascinating and important event which is likely to trigger a race to be the first to record the phenomenon.
Dr Robert Massey, of the Royal Astronomical Society, said: "What we're talking about you might literally call the birth of a new star which should be very visible.
"The good news for people in the UK is that it is in the constellation Cygnus which is always above the horizon and is very high in the sky in the summer, so everyone will be able to see it.
"Nobody has ever managed to predict the birth of a star before so this is really unprecedented and I think there will be a race among amateur astronomers, and members of the public to spot it first."
The forecast was made officially at a press conference on Friday, all the more poignant because it coincided with the epiphany, which commemorates the visit of the Three Wise Men, who followed the star to Bethlehem to witness the birth of Jesus.
The binary star system, named KIC9832227, is 1,800 light years away and is made from two suns which spin around each other every 11 hours.
In 2013 Professor Larry Molnar and his team at Calvin College noticed that the orbital speed was decreasing. And doing so faster and faster.
It matched the data from another binary star which exploded in 2008 without warning and was picked up by astronomers. When experts went back over data from previous years they discovered that the crash could have been predicted because of the increasing orbital speeds.
"Observations of KIC9832227 show its orbital period has been getting faster since 1999 in the same distinctive way. We arrive at our predicted date by assuming the same process is happening here," said Prof Molnar, who is professor in astronomy.
"The star is around 1800 light years. Hence if we are right about the upcoming outburst, it actually occurred 1795 years ago, and the light from the outburst has been travelling toward us ever since.
"Explosions of this size occur about once a decade in our Galaxy. This case is unusual in how close the star is and hence how bright we will see it shine and unique in that it is the first time anyone has predicted an explosion in advance.
"It's a one-in-a-million chance that you can predict an explosion. It's never been done before."
Not only will be the event be an amazing spectacle for stargazers, it will also give scientists an unprecedented opportunity to observe the process as it unfolds. Astronomers do not understand the details of why stars merge or even how the explosions work.
"If Larry's prediction is correct, his project will demonstrate for the first time that astronomers can catch certain binary stars in the act of dying, and that they can track the last few years of a stellar death spiral up to the point of final, dramatic explosion," added Dr Walhout.
The work was presented at the annual American Astronomy Association meeting in Grapevine, Texas