Astronomers have spotted the brightest fast radio burst ever recorded – and they say it will help finally pinpoint the source of the strange ‘alien signals’.
Fast radio bursts are brief, bright pulses of radio emissions and they have baffled astronomers for almost a decade.
Since they were first found in 2007, scientists have been unable to determine the origin of the radio emissions, which last just a few milliseconds.
Some claim they may be a message from ET, while others suggest they are created by a neutron star cocooned by a strong magnetic field.
So far, only 33 FRBs have been detected, but two groups of researchers have uncovered three more in recent days.
The first was discovered by Breakthrough Listen, which looks for signs of intelligent life in the universe and has been funded with $100 million (£75 million) of investment over ten years from internet mogul Yuri Milner.
The second and third were identified by a team of researchers at the Swinburne University of Technology in Melbourne, Australia, on March 9 and 11.
The flash discovered on March 9 is around 4.5 times brighter than the next brightest signal ever uncovered according to the FRB Catalogue, a list of FRBs compiled by the Netherlands Institute for Radio Astronomy.
All three FRBs were found using Australia’s Parkes Telescope.
‘Finding three this quickly is quite unusual,’ Peter Williams, of the Harvard-Smithsonian Center for Astrophysics, told New Scientist. ‘It seems like it was just luck.’
Only one FRB in the catalogue has been detected flashing more than once, but some researchers believe all FRBs repeat, with some too dim for us to see all of their flashes.
WHAT ARE FAST RADIO BURSTS AND WHY DO WE STUDY THEM?
Fast radio bursts, or FRBs, are radio emissions that appear temporarily and randomly, making them not only hard to find, but also hard to study.
The mystery stems from the fact it is not known what could produce such a short and sharp burst.
This has led some to speculate they could be anything from stars colliding to artificially created messages.
The first FRB was spotted, or rather ‘heard’ by radio telescopes, back in 2001 but wasn’t discovered until 2007 when scientists were analysing archival data.
But it was so temporary and seemingly random that it took years for astronomers to agree it wasn’t a glitch in one of the telescope’s instruments.
Researchers from the Harvard-Smithsonian Center for Astrophysics point out that FRBs can be used to study the structure and evolution of the universe whether or not their origin is fully understood.
A large population of faraway FRBs could act as probes of material across gigantic distances.
This intervening material blurs the signal from the cosmic microwave background (CMB), the left over radiation from the Big Bang.
A careful study of this intervening material should give an improved understanding of basic cosmic constituents, such as the relative amounts of ordinary matter, dark matter and dark energy, which affect how rapidly the universe is expanding.
FRBs can also be used to trace what broke down the ‘fog’ of hydrogen atoms that pervaded the early universe into free electrons and protons, when temperatures cooled down after the Big Bang.
Some researchers have hypothesised that all FRBs repeat, and that they’re too dim for us to see all of the bursts.
Maura McLaughlin at West Virginia University in Morgantown, added that the March 9 FRB’s unusual brightness should make future detections easier if the repeating FRB hypothesis is correct.
She also believes future detection of further FRBs should be forthcoming, given that there are now so many people on the lookout for them.
Professor McLaughlin said: ‘Everyone’s sort of jumping on this bandwagon of looking for FRBs in the background all the time no matter what else is going on.
‘This should lead to a huge uptick in detections in the next year or so.’
FRBs were first detected in 2007 by experts scouring archival data from the Parkes Telescope dating back to 2001.
The 200 foot (64 metre) diameter dish is best known for its role receiving live television images from the Apollo 11 moon landing in 1969.
But the antenna’s detection of the first FRB, and the subsequent confirmed discovery of more than two dozen of the powerful radio pulses across the sky, left astrophysicists baffled.
The catch with FRBs is that they are mostly random and they last for only a few milliseconds – too fast to routinely detect or conduct follow-up observations with radio and optical telescopes.
Only one FRB has been found to repeat, an object known as FRB 121102 in a galaxy about three billion light-years away.
ARE MYSTERIOUS FAST RADIO BURSTS SIGNALS FROM ALIEN EXPLORERS?
Mysterious signals coming from distant galaxies could be evidence of deep-space explorers billions of light-years from Earth, a recent study has claimed.
Researchers from the Harvard-Smithsonian Center for Astrophysics in March 2017 claimed a solar-powered transmitter using sunlight cast on an area twice the size of Earth could generate enough energy to be ‘seen’ by far away viewers.
And, a water-cooling system would allow a device of this size to withstand the extreme heat.
The researchers argue that the most plausible use for this tremendous amount of power would be to drive interstellar light sails.
The light sail would rely on a steady beam from the transmitter.
While this would always be pointed at the sail, observers on Earth would see it as a brief flash, as the sail, its host planet, its star, and the galaxy all move relative to us.
This would cause the beam to sweep across the sky, only pointing at Earth for a moment.
More than 200 high-energy bursts have been observed coming from FRB 121102, since it was first detected in 2012.
In January, an international team of researchers used the Robert C. Byrd Green Bank Telescope in West Virginia to study FRB 121102.
They found that the electromagnetic waves that make up the bursts generated by the object conform to a highly unique pattern.
This means they came from somewhere with an incredibly strong magnetic field, like that found around a black hole or neutron star.
Such patterns have only ever been seen in radio emissions from the extreme environments around massive black holes, such as those at the centres of galaxies.
The findings confirm observations by another team of astronomers from the Netherlands, which detected the polarised bursts using the William E. Gordon Telescope at the Arecibo Observatory in Puerto Rico.
The Dutch and Breakthrough Listen teams suggest that the FRBs may come from a highly magnetised rotating neutron star – known as a magnetar – in the vicinity of a massive black hole that is still growing as gas and dust are sucked into it.
Another possibility, though remote, is that the FRB is a high-powered signal from an advanced civilisation.