Astronomers detect FIVE fast radio bursts from over 4 billion light years away
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Of all the mysterious astronomical phenomena, none have generated such excitement in recent years as fast radio bursts, or FRBs.
Recorded in the radio band of the electromagnetic spectrum, these strangely bright flashes of light appear momentarily and randomly from space.
Possibly from black holes, neutron stars or even aliens, they range from a fraction of a millisecond to several seconds before disappearing without a trace.
Now researchers have announced that they have detected five new FRBs thanks to an upgrade of the Westerbork Synthesis Radio Telescope in the Netherlands.
As they traveled through space to Earth, three of these FRBs pierced our neighboring Triangulum Galaxy, a spiral galaxy about 2.73 million light-years away.
Five new fast radio bursts discovered by the Westerbork telescope in the Netherlands have been detected, a new study shows (artist’s impression)
The new FRBs were discovered in 2019, but have only now been detailed in a new paper by an international team led by Joeri van Leeuwen from the University of Amsterdam.
“Fast radio bursts (FRBs) must be driven by unique energetic emission mechanisms,” the team says in their paper.
“We discovered five new FRBs, an important addition to the 100 or so that appeared at the time.”
FRBs are radio waves, so they can’t be seen by the human eye, but they’re not uncommon.
They come from all over the sky, but have perplexed researchers for years because their cause is little understood.
It’s possible they’re emitted from neutron stars — the collapsed cores of a few massive stars that pack roughly the mass of our sun into a city-sized region.
But scientists have also suggested that they could be artificial signals created by intelligent beings.
In 2017, a team from the Harvard-Smithsonian Center for Astrophysics said they could have come from distant alien transmitters that power interstellar probes.
Professor Avi Loeb of the institute said at the time that an artificial origin of these signals “is worth considering”.
If a single FRB goes off, it contains 10 trillion times the annual energy consumption of the entire world’s population.
The flashes are so powerful that radio telescopes can detect them more than four billion light-years away.
But studying FRBs is difficult because no one knows where in the sky the next eruption will occur.
Plus, they usually only last a millisecond (although last year experts announced the discovery of one that lasts three seconds, 1,000 times longer than the average).
Researchers discovered the new FRBs with the Westerbork Synthesis Radio Telescope in the Netherlands (photo)
Experts therefore rely on ground-based telescopes stationed around the world to detect these transient radio pulses as they occur.
Astronomers had upgraded the radio telescope array at Westerbork with a new supercomputer, the Apertif Radio Transient System (ARTS).
Westerbork – built on the site of the former World War II Nazi camp – contains 14 saucers, each 25 meters in diameter.
This upgrade, according to the team, was equivalent to changing the array’s visual quality to that of a fly to an eagle.
‘You can’t just buy the complex electronics you need for this,’ says study author Eric Kooistra of the Netherlands Institute for Radio Astronomy.
‘We largely designed the system ourselves, with a large team. That resulted in a state-of-the-art machine, one of the most powerful in the world.’
The ARTS supercomputer now continuously combines the images from 12 Westerbork dishes into a sharp image over an enormous field of view.
Previously, radio telescopes could only roughly indicate where an FRB occurred, but ARTS now allows experts to pinpoint the exact location of an FRB.
FRBs are known to pierce other galaxies on their way to Earth, and electrons in those galaxies, normally mostly invisible, distort the flashes.
Tracking down invisible electrons and their companion atoms is important because most of the matter in the universe is dark and we still know little about it.
The Triangulum Galaxy, also known as Messier 33, as captured by NASA’s Hubble Space Telescope
Researchers found that as the five FRBs traveled through space, three “cut well through” the halo of the Triangulum galaxy, also known as M33.
They then intersected the halo of the much larger Andromeda Galaxy (M31), which is close to M33, and finally the halo and disk of our own Milky Way.
Sharp new images allowed astronomers to estimate the maximum number of invisible atoms in Triangulum for the first time.
The team now wants to learn more about how and why FRBs can become so smart – and their mysterious origins.
The research has been published in the journal Astronomy & Astrophysics.
RAPID RADIO BURSTS ARE BRIEF RADIO EMISSIONS FROM SPACE WHOSE ORIGIN IS UNKNOWN
Fast radio bursts, or FRBs, are radio emissions that appear momentarily and randomly, making them not only hard to find, but also hard to study.
The mystery stems from the fact that it is not known what could cause such a short and sharp burst.
This has led some to speculate it could be anything from colliding stars to artificially created messages.
Scientists are looking for fast radio bursts (FRBs) that some believe are signals sent by aliens that could be happening every second. The blue dots in this artist’s impression of the filamentary structure of galaxies are signals from FRBs
The first FRB was spotted, or rather “heard,” by radio telescopes in 2001, but was not discovered until 2007 when scientists were analyzing archival data.
But it was so temporary and seemingly random that it took astronomers years to agree it wasn’t a malfunction in one of the telescope’s instruments.
Researchers at 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 origins are fully understood.
A large population of distant FRBs could act as probes of material over gigantic distances.
This intermediate material blurs the signal from the cosmic microwave background (CMB), the leftover radiation from the Big Bang.
A careful study of this intermediate material should yield a better understanding of basic cosmic constituents, such as the relative amounts of ordinary matter, dark matter and dark energy, that affect how fast the universe is expanding.
FRBs can also be used to track what the “fog” of hydrogen atoms that permeated the early universe broke down into free electrons and protons as temperatures cooled after the Big Bang.