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News Article | May 25, 2017
Site: www.sciencedaily.com

A CSIRO telescope in Western Australia has found its first 'fast radio burst' from space after less than four days of searching. The discovery came so quickly that the telescope, the Australian Square Kilometre Array Pathfinder (ASKAP) near Geraldton in Western Australia, looks set to become a world champion in this fiercely competitive area of astronomy. The new fast radio burst finding was published in the Astrophysical Journal Letters. 'Fast radio bursts' or FRBs are short, sharp spikes of radio waves lasting a few milliseconds. They appear to come from powerful events billions of light-years away but their cause is still a mystery. The first was discovered in 2007 and only two dozen have been found since. The discovery of the new burst, FRB170107, was made by CSIRO's Dr Keith Bannister and his colleagues from CSIRO, Curtin University and the International Centre for Radio Astronomy Research (ICRAR) while using just eight of the telescope's 36 dishes. The discovery is the culmination of a decade of science and engineering development by CSIRO and Curtin University. "We can expect to find one every two days when we use 12 dishes, our standard number at present," Dr Bannister said. To make the most recent detection, the researchers used an unusual strategy. "We turned the telescope into the Sauron of space -- the all-seeing eye," Dr Bannister said, referring to the dark overlord in Tolkien's "Lord of the Rings." Usually ASKAP's dishes all point at the one part of sky. But they can be made to point in slightly different directions, like the segments of a fly's eye. This multiplies the amount of sky the telescope can see. Eight ASKAP dishes can see 240 square degrees at once -- about a thousand times the area of the full Moon. The new burst was found as part of a research project called CRAFT (Commensal Real-time ASKAP Fast Transients survey), which is led jointly by Dr Bannister and Dr Jean-Pierre Macquart from the Curtin University node of ICRAR. Dr Macquart said the new burst was extremely bright and that finding it was "as easy as shooting fish in a barrel." FRB170107 came from the edge of the constellation Leo. It appears to have travelled through space for six billion years before slamming into the WA telescope at the speed of light. The burst's brightness and its apparent distance mean that the energy involved is enormous, making it extremely challenging to explain. "We've made a hard problem even harder," said Dr Ryan Shannon (CSIRO, Curtin University and ICRAR), who analysed the burst's strength and position. CSIRO Chief Executive Dr Larry Marshall said the FRB detection was a sign of the full potential of ASKAP. "Radio astronomy has a long history of innovation in high-speed communications, and this unique capability is embedded into ASKAP -- from the receiver to the signal processing -- making it a uniquely powerful instrument for astronomy," Dr Marshall said. In addition to the discovery of the new burst, Dr Bannister has a big reward -- a happy family. He'd been telling his three kids for months about his plans. "Every day as I left for work they'd ask, 'Are you going to find a radio burst today, Daddy?'" he said. And when it finally happened, "they were too excited for words." "They just looked at me, smiled, and gave me a great big hug!"


This article was originally published on The Conversation. Read the original article. They’re mysterious bursts of radio waves from space that are over in a fraction of a second. Fast Radio Bursts (FRBs) are thought to occur many thousands of times a day, but since their first detection by the Parkes radio telescope a decade ago only 30 have been observed. But once the Australian Square Kilometre Array Pathfinder (ASKAP) joined the hunt, we had our first new FRB after just three and half days of observing. This was soon followed by a further two FRBs. And the telescope is not even fully operational yet. Trending: Michael Rubin: Why are Erdogan’s Thugs Running Free in DC? The fact that ASKAP detects FRBs so readily means it is now poised to tackle the big questions. One of these is what causes an FRB in the first place. They are variously attributed by hard-nosed and self-respecting physicists to everything from microwave ovens, to the accidental transmissions of extraterrestrials making their first baby steps in interstellar exploration. The astounding properties of these FRBs have so enthralled astronomers that, in the decade since their discovery, there are more theories than observed bursts. FRBs are remarkable because they are outrageously bright in the radio spectrum yet appear extremely distant. As far as astronomers can tell, they come from a long way away—halfway across the observable universe or more. Because of that, whatever makes FRBs must be pretty special, unlike anything astronomers have ever seen. What has astronomers really excited is the fossil record imprinted on each burst by the matter it encounters during its multibillion-year crossing of the universe. Matter in space exerts a tiny amount drag on the radio waves as they hurtle across the universe, like the air drags on a fast-moving plane. But here’s the handy bit: the longer the radio waves, the more the drag. By the time the radio waves arrive at our telescopes, the shorter waves arrive just before the longer ones. By measuring the time delay between the short waves and the longer ones, astronomers can work out how much matter a given burst has travelled through on its journey from whatever made it, to our telescope. Don't miss: Pope Francis and President Trump: A Brief History of Their War of Words If we can find enough bursts, we can work out how much ordinary matter—the stuff you and I and all visible matter is made of—exists in the universe, and tally up its mass. The best guess so far is that we are missing roughly half of all the normal matter, with the rest lying in the vast voids between the galaxies—the very regions so readily probed by FRBs. Are FRBs the weigh stations of the cosmos? There are a few reasons why we still have so many questions about FRBs. First, they are tricky to find. It takes the Parkes telescope around two weeks of constant watching to find a burst. Worse, even when you’ve found one, many radio telescopes like Parkes can only pinpoint its location in the sky to a region about the size of the full Moon. If you want to work out which galaxy an FRB came from, you have hundreds to choose from within that area. The ideal FRB detector needs both a large field of view and the ability to pinpoint events to a region one thousandth the area of the Moon. Until recently, no such radio telescope existed. Now it does in ASKAP, a radio telescope being built by the CSIRO (Commonwealth Scientific and Industrial Research Organisation) in Murchison Shire, 370km (230 miles) northeast of Geraldton in Western Australia. It’s actually a network of 36 antennas, each 12 metres in diameter.


News Article | May 25, 2017
Site: www.newscientist.com

Talk about rocking the cradle. Sharp new images have identified a throng of newborn stars as the source of a fast radio burst. The discovery strengthens the idea that these brief pulses of radio waves arise from newly formed neutron stars, super-dense objects just 20 kilometres across. During the past decade, astronomers have detected about two dozen fast radio bursts from all over the sky. Each lasts just a few milliseconds, and attempts to explain them have invoked everything from supermassive black holes to little green men. Until recently, we didn’t even know for sure whether the bursts arose in our galaxy or beyond. But in January, researchers announced a breakthrough. They found the home of a fast radio burst named FRB 121102: a small galaxy in the constellation Auriga 2.4 billion light years from Earth. Now, Cees Bassa of the Netherlands Institute for Radio Astronomy in Dwingeloo and his colleagues have used the Hubble Space Telescope to study the galaxy. “The Hubble observations allow us to get a very sharp image,” says team member Shriharsh Tendulkar of McGill University in Montreal, Canada. “There is a very bright spot of star formation, and this FRB lies bang inside it.” Meanwhile, Japanese astronomers led by Mitsuru Kokubo of Tohoku University in Sendai used the 8.2-metre Subaru Telescope in Hawaii to target the galaxy. Their images rival Hubble’s because adaptive optics undid the usual blurring created by Earth’s atmosphere. The Hubble and Subaru images show that the star-forming complex lies on the small galaxy’s outskirts. Hubble’s handiwork puts the galaxy’s visible diameter at about 20,000 light years, one-sixth that of the Milky Way. The stellar nursery is 6200 light years from the galaxy’s centre and spans 4400 light years, far larger than any known in the Milky Way. “It’s an extraordinary galaxy,” says Dale Frail of the National Radio Astronomy Observatory in Socorro, New Mexico. “Relative to its small size, it’s making stars at a prolific rate.” That points to the cause of fast radio bursts. “It’s telling us that they probably occur in young neutron stars,” says Jonathan Katz of Washington University in St Louis, Missouri. Many astronomers already favour that explanation because the short duration of the bursts suggested the source was tiny. Neutron stars fit the bill, and young, fast-spinning ones have plenty of energy to release. They form when short-lived massive stars die in their stellar nurseries. But no one yet knows whether the same idea explains other fast radio bursts. FRB 121102 is unique: astronomers have seen it flash about 30 times but the others only once. Katz suspects they may all have the same cause, but Frail says, “I would be reluctant to draw such broad conclusions based on a sample of one.”


News Article | May 26, 2017
Site: www.cnet.com

Fast radio bursts from space are a uniquely 21st-century mystery. They were first identified just 10 years ago and, up until very recently, we've only caught about two dozen of them. But a new telescope in Australia is already making it much easier to detect fast radio bursts, or FRBs, which makes this an appropriate time to delve into some key questions. For instance, what the heck is an FRB and where do they come from? FRBs are essentially just what they sound like -- radio signals from somewhere in deep space that last for just milliseconds. "Fast radio bursts are exceedingly bright given their short duration and origin at great distances, and we haven't identified a possible natural source with any confidence," Avi Loeb, a Harvard-Smithsonian Center for Astrophysics theorist, said in a press release in March. As with most space stuff that can't yet be explained without a doubt by some natural phenomenon, aliens have been proposed as a possibility, including by Loeb himself. "An artificial origin is worth contemplating and checking," he says. Loeb and his colleagues worked out how much power would be needed to send such signals across the universe. Turns out it would require covering two Earth-size planets with energy collectors, leading Loeb to theorize that such a massive project might be used not to communicate, but to propel starships using high-energy beams. While aliens might be the most exciting possible explanation, that doesn't mean they're the most probable. There are, after all, natural phenomena in the cosmos that could generate such signals and are known to actually exist, which is more than we can say for extraterrestrials. Exploding black holes, magnetars, neutron stars and hypothetical blitzars are just a few of the exotic possible causes that could be throwing off radio emissions that eventually make it to us. One aspect of FRBs that has made them so hard to trace back to a source is that they rarely seem to repeat. They're just detected and never heard from again. That is, until January when researchers announced they'd finally identified that FRB 121102 repeats. This allowed them to trace the blinking signal to a surprising source: a distant dwarf galaxy 3 billion light-years beyond the Milky Way. "That's weird isn't it? You'd expect to find FRBs where there are more stars ... more stars means more neutron stars," Shriharsh Tendulkar of McGill University and the discovery team said in January. It's also weird because a signal that distant would have originated so long ago that Earth would have still been a largely lifeless rock at the time. This lends credence to the idea that FRBs might be like the aftershocks of cosmic cataclysms from when the universe was much younger. Or maybe there are different types of FRBs out there or different explanations we haven't even thought of yet. At least one case of an FRB was later explained by someone at an observatory opening a microwave oven door while it was running. Clearly, it's still early days for the study of fast radio bursts, but the new Australian Square Kilometre Array Pathfinder and other upcoming next-generation observatories could help solve the mystery or at least provide some more solid clues. Technically Literate: Original works of short fiction with unique perspectives on tech, exclusively on CNET.


News Article | May 23, 2017
Site: www.gizmag.com

Mysterious radio signals from space have been coming in from all directions, and their source is still unknown. Extremely bright and short-lived, these fast radio bursts (FRB) have scientists puzzled, but the Australian Square Kilometer Array Pathfinder (ASKAP) radio telescope may help bring some answers to light. New Atlas spoke to Keith Bannister, an astronomer on the project, about what might be behind these strange signals and how the mystery might be unraveled. Located in an isolated part of Western Australia, far from the radio interference of the city, one of ASKAP's main goals is to study FRB, and it picked up its first one just four days after it began the search, in January this year. Designated FRB170107, the signal originated from the constellation of Leo, and traveled some six billion light-years to get here. "Scientists aren't very original at naming things: they're fast, and they're radio, and they're bursts," Bannister explains to us. "So they're radio, you detect them with a radio telescope that looks like a big satellite dish. And they're fast – really fast. Click your fingers and they're gone, less than a millisecond usually in duration. And they're bursts. They happen once and that's the last time we see them." The first FRB was identified in 2007, when scientists trawling through archival data from 2001 came across a short, sharp burst that couldn't be explained. Over the next few years, more of these anomalies were discovered in existing data, but the phenomenon wasn't detected live until 2015. In total, less than 30 of the signals have been identified so far. Generally, astronomers aren't sure what could be giving off these signals, but they seem to have the most in common with pulsars and magnetars. These two types of neutron stars both have extremely large magnetic fields and give off similar radio bursts, but the difference is that they repeat themselves. Some are as regular as clockwork while others have more unpredictable patterns, but either way they usually happen more than once. FRB, on the other hand, are largely one-time events, and that leaves scientists scratching their heads over their origins. "There are more theories than there are bursts," says Bannister. "They range from everything from scaled-up versions of what we've seen in our own galaxy, like a pulsar or a magnetar, to things that are much more exotic: someone proposed it's the signal of what alien civilizations look like when they're starting to explore their own galaxy." While these outlandish ideas often pop up to help explain space mysteries, the general consensus tends to lean toward something a little more mundane. "The community at the moment hasn't really settled on anything," says Bannister. "But the more conservative theory people are saying it's probably got to be something to do with a neutron star. So you can think of a pulsar as being a neutron star with a huge magnetic field, and then a magnetar is a neutron star with an even bigger magnetic field. So maybe if you can make one that's got an even bigger magnetic field, then eventually it can make FRB. That I think is probably the leading option, but it's not settled by any stretch." The first steps toward answering the question of what FRB are is simply to find more of them. The more data there is to work with, the clearer the picture gets, and being able to detect them faster means more telescopes can be trained on that patch of sky to see what possible points of origin are lurking there. "One big leap forward will be when a fast radio burst happens, to really pinpoint its location in the sky," says Bannister. "Then you can go and look and see if there's a galaxy there, and that will tell you a lot. So if it turns out FRB come from certain types of galaxies, then we can use what we know about those galaxies to try and work out what FRB are. We'll go back and we'll look for repeats. We take optical images, we look for x-ray images or gamma ray bursts, or all sorts of stuff. So once you start finding them, you can go back and look in that particular part of the sky with lots of different types of telescopes, and see what you can see." By the same token, the more FRB that are studied, the more likely it becomes that a particularly enlightening one will be spotted. "When you look at enough bursts, you never know when one of them is so unusual it kind of unlocks the whole thing," says Bannister. "So in that sense, jut collecting more sometimes is helpful because every now and then you'll find one that's a real oddball, and that actually turns out to be the key to understanding the whole bunch." In fact, the oddball in question may have already been discovered. FRB121102 was first found by the Arecibo radio telescope in Puerto Rico, and so far it's the only fast radio burst to buck the trend of being a one-hit wonder, instead pulsing at least 16 times since its discovery in 2012. Whether it confounds the mystery or helps solve it remains to be seen. "That's the oddball of the family," says Bannister. "We call it the Repeater, because there's only one. That's even more puzzling than the phenomenon of fast radio bursts. We think they're probably connected, but we don't exactly know how." Besides the thrill of nailing down a potentially new type of celestial object, FRB can give us a new understanding of our little corner of the Universe. They travel an extremely long distance through space before they reach us, and when they get here they carry with them clues about their journey. "The key property of radio bursts in general, from pulsars and fast radio bursts, is that we can measure what's called the dispersion," says Bannister. "So the radio waves as they leave the pulsar or fast radio burst, they go at different speeds, and that's because of the matter that the radio waves are going through. When they get to our telescopes, the short wavelengths arrive first and the long wavelengths about a second afterwards, and that time delay tells us how much matter those waves have gone through." By that system, when a fast radio burst is found to have a large dispersion, that indicates that the radio waves have passed through a lot of electrons. Astronomers can then compare that data with what they know about that region of the sky, and if there aren't many galaxies in its path, it tells them that the signal must have come from a long way away. When a fast radio burst goes off, studying its dispersion can tell scientists just how much matter there is along that line of sight, and with enough data, a 3D map of the Universe can effectively be built up. ASKAP began searching for FRB in the first week of January this year, and within four days it had spotted its first signal. Since then two more FRB have been detected, and that was done using just eight of its eventual 36 dishes. Those dishes, each 12 m (40 ft) in diameter, will all point in slightly different directions, giving the array a wide viewing area, like a segmented fly's eye. "This thing will see 36 different patches of the sky at the same time," says Bannister. "That's a huge increase in the amount of sky you can see, and that makes a huge difference in how many FRB you can catch every day." The rest of these dishes are due to come online over the next 12 to 18 months, and when that happens, the number of FRB the system spots should increase dramatically. "I think the next 12 months will be a pretty exciting time, because there are a lot of telescopes, like ASKAP, that are just starting up, and once they're really running, there'll be a lot of new information coming in," says Bannister. A paper describing the ASKAP team's discovery was published in The Astrophysical Journal Letters.


A new mystery signal from deep space has been detected, leaving scientists baffled as to where it came from and what caused it. The signal, known as a fast radio burst (FRB), was detected in 2015 by scientists using the Parkes radio telescope in Australia. It adds to the two dozen other FRBs previously recorded. But this one, known as FRB 150215, is even stranger than those that came before it. FRBs are radio signals that last just a few milliseconds. They appear to be coming from deep space, but because of their extremely short duration—and because scientists normally only notice them in data after the event has taken place—their origin remains a mystery. The first FRB was detected in 2001. Since then, at least 20 other bursts have been recorded. One of these, FRB 121102, was found to repeat, with 16 bursts coming from the same direction in space. This allowed scientists to hone in on their location, finding that they were emanating from an unassuming small galaxy over three billion light-years away. But this still did not help scientists pinpoint their source—no known nearby object could have been producing the FRBs. Scientists have several theories about the source of FRBs. One is that they are caused by a cataclysmic event, such as a neutron star collapsing into a black hole or supernova. Another potential source is a young, highly magnetised neutron star. Neither, however, fully explains the FRBs recorded because a one-off high energy event like a collapsing star would not be able to produce repeating bursts. Don't miss: Why Did Rosenstein Agree To Take Part in the Comey Farce? Now, researchers led by Emily Petroff from the Netherlands Institute for Radio Astronomy, have announced the discovery of another, even stranger FRB. Their study appears on Cornell University’s online server where scientists can share their research before it is formally published. In it, the team describe FRB 150215, which they were able to catch in real time, meaning immediate follow-up observations could be made to try and catch the source in action. This burst is unusual because scientists should not have been able to detect it at all. The Milky Way’s magnetic field, which the burst travelled through on its way to Earth, should have changed the way the FRB travelled. But this did not happen. In an interview with Gizmodo, Petroff explained: “It probably traveled through some kind of hole in the Milky Way that makes it easy to find compared to normal searches in the galaxy.” Most popular: Trump and Russia: What Constitutes an Independent Investigation? After the FRB was detected, the team carried out extensive follow-up observations in the hope of spotting the event that caused it. The array of telescopes used effectively means the team were covering as many cosmic bases as they could—different observations would pick up different potential sources. “We spent a lot of time with a lot of telescopes to find anything associated with it,” Petroff said. “We got new wavelength windows we’ve never gotten before. We looked for high-energy gamma rays and neutrinos...we ruled out some source classes but no detection is a little unhelpful. We’re still trying to figure out where this one came from.” Commenting on the study, Shami Chatterjee, from the Cornell Center for Astrophysics and Planetary Science, told the website: “I have to say this is a fantastic paper but it is a bummer of a paper. They threw every resource that we have at this FRB...and they see nothing. It is incredibly important in the sense that even with relatively prompt follow-up there isn’t an afterglow or counterpart that is obvious.” Responding to questions about the source potentially being an advanced alien civilisation, Petroff said: “Just to be clear, we don't know what is causing the fast radio bursts we see, but we don't think it's anything to do with aliens!”


Researchers from around the world are scratching their heads over a newly discovered radio burst detected on Earth, but with a completely unknown origin. A new report describing the event and the subsequent investigation is now available online, but the key takeaway is that despite our best efforts and wealth of technology employed to discover the source, humanity has simply come up short. What’s even more bizarre is that this isn’t the first time it’s happened. Don't Miss: Amazon just discounted the Echo for the first time in 2017 Scientists call them “fast radio bursts,” or FRBs for short, and they’ve been confounding researchers for some time now. This newest burst, labeled FRB 150215 is the latest of 22 detected FRBs thus far, but it’s also the most frustrating for those hunting for the source. FRB 150215 was first detected in Australia by scientists running the Parkes Telescope, but once the radio burst arrived, many other research groups with their own powerful telescopes sprung into action in search of the source. Despite their best efforts, nobody has been able to figure out where the radio burst originated, which is odd for a number of reasons, but the strangest thing about FRB 150215 — and FRBs in general — is that anything powerful enough to produce a radio burst that could be detected on Earth, yet remain completely out of sight, must be absolutely massive in scale. Some scientists have theorized that the burst are created by supernovas, and that because the light of the event reaches Earth long before the radio waves, the source appears to have vanished. Of course, there are plenty of theories that hinge on the possibility of intelligent alien life attempting to make contact with other civilizations, but if that is indeed the case, we’re going to have one heck of a time trying to find them. See the original version of this article on BGR.com


News Article | May 12, 2017
Site: phys.org

FRBs are a relatively new development for space scientists—they are extremely short blasts of strong radio waves that come from space, but scientists have not been able to explain what makes them. In this new detection, the FRB, now named FRB 150215, was first detected by researchers working with the Parkes Telescope in New South Wales, Australia. What made the detection of FRB 150215 unique was that several teams were prepared to train their telescopes on the FRB origin point shortly after it was detected. Unfortunately, none of them were able to detect anything that might identify its cause, or even exactly where it occurred. exactly. Additionally, after analyzing data from the follow-up telescopes, the researchers found that the FRB had taken an interesting path through the Milky Way to make its way to us—a hole of sorts that, prior to the detection of the FRB, was unknown. Thus, despite learning nothing new about the source of FRBs in general, the team has learned something new about our galaxy. The detection of FRB 150215 marks the detection of 22 FRBs to date, none of which have identifiable sources, making them one of the great mysteries of space science. Common sense suggests that finding a source should be relatively easy—it would take something pretty big to create such strong pulses of radio waves. The mysterious nature of FRBs has led to a host of theories regarding their nature, from supernova to intelligent alien communications. Others suggest the research into finding the source of FRBs has been unsuccessful because space scientists are looking at the problem backwards—FRBs, they note, could arise long after the precipitating event. That means it might make more sense to look for noticeable events in the night sky, like supernovas, and then monitor for FRBs sometime later. In any event, study of FRBs is likely to increase as the mystery deepens and new telescope technology emerges—some have even suggested that it is possible that FRBs are much more common than has been shown, and that once they are observed more regularly, researchers can focus on looking at patterns. Explore further: Mysterious bursts of energy do come from outer space Abstract We report on the discovery of a new fast radio burst, FRB 150215, with the Parkes radio telescope on 2015 February 15. The burst was detected in real time with a dispersion measure (DM) of 1105.6±0.8 pc cm^{-3}, a pulse duration of 2.8^{+1.2}_{-0.5} ms, and a measured peak flux density assuming the burst was at beam center of 0.7^{+0.2}_{-0.1} Jy. The FRB originated at a Galactic longitude and latitude of 24.66^{circ}, 5.28^{circ}, 25 degrees away from the Galactic Center. The burst was found to be 43±5% linearly polarized with a rotation measure (RM) in the range -9


The search for fast radio burst could be bolstered by citizen scientists using their mobile phones. A team of researchers has said a global network of phones and small radio receivers could be used to detect these mystery signals emanating from an unknown source in space. In a report that has been accepted for publication in the Monthly Notices of the Royal Astronomical Society, scientists from the Harvard-Smithsonian Centre for Astrophysics (CfA) and Tel Aviv University say if such a network were in place, it could be used to detect a simultaneous radio blip. This blip would indicate a FRB has been recorded – coming from inside the Milky Way. FRBs are radio signals coming from unknown sources deep in space. Lasting just a few milliseconds, scientists have struggled to identify their origin – the few dozen that have been detected were identified from data after the event, meaning their origin could not be traced back. At present, only one FRB has been found to repeat. In total, scientists have recorded 16 bursts coming from FRB 121102 – meaning they could be tracked to a galaxy three billion light years away. But even though we now know the location, we still do not know what is causing these bursts. The search for more FRBs continues, with astronomers across the globe using huge radio telescopes to detect them. The team say this presents an opportunity to harness a global collective of citizen scientists to look out for FRBs from within our own galaxy. While other FRBs appear to be coming from deep space, there is no reason to think one could not emanate closer to home. "An FRB in the Milky Way, essentially in our own back yard, would wash over the entire planet at once. If thousands of cell phones picked up a radio blip at nearly the same time, that would be a good sign that we've found a real event," said lead author Dan Maoz of Tel Aviv University. How it would work: We propose to search for Galactic FRBs using a global array of low-cost radio receivers. Participating phones would continuously listen for and record candidate FRBs and would periodically upload information to a central data processing website, which correlates the incoming data from all participants, to identify the signature of a real, globe-encompassing, FRB from an astronomical distance. Triangulation of the GPS-based pulse arrival times reported from different locations will provide the FRB sky position, potentially to arc-second accuracy. Pulse arrival times from phones operating at diverse frequencies, or from an on-device de-dispersion search, will yield the dispersion measure (DM) which will indicate the FRB source distance within the Galaxy. FRBs have been detected at frequencies that match those used by mobile phones and Wi-Fi. Potentially, people could download an app that would constantly be running in the background, monitoring frequencies. It could then send data to a central processing facility where any abnormalities could be identified. The researchers calculate there might be FRBs in the Milky Way once every 30 to 1,500 years. But if it is a repeating burst – like FRB 121102 – it may pop up every week. "If FRBs originate from galaxies at cosmological distances, then their all-sky rate implies that the Milky Way may host an FRB on average once every 30 to 1,500 years," they wrote. "If FRBs repeat for decades or centuries, a local FRB could be active now." Avi Loeb, from the CfA, said: "The search for nearby fast radio bursts offers an opportunity for citizen scientists to help astronomers find and study one of the newest species in the galactic zoo."


News Article | February 15, 2017
Site: www.newscientist.com

For the first time, we have followed a fast radio burst home. While we’re still not sure what causes these brief barrages of radio waves, we now know where one of them comes from, giving us a new way to study their origins. Fast radio bursts (FRBs) are some of the universe’s most elusive phenomena: powerful radio signals that flash from distant space for milliseconds and then disappear without a trace. They have been blamed on everything from black holes to extraterrestrial intelligence. Because they’re so brief, and because radio telescopes can only watch a small area of the sky at a time, only 18 FRBs have ever been detected. Of those, only one has been observed to repeat: FRB 121102. Now, a team of astronomers has used a collection of radio telescopes around the globe to finally pinpoint this repeating burst. “It is absolutely nailed down,” says Shami Chatterjee at Cornell University in Ithaca, New York, who presented the results at a meeting of the American Astronomical Society in Grapevine, Texas today. “Even two months ago, I did not think we could tell this full story, and now we can.” Chatterjee and his colleagues tracked down the FRB using the Karl G. Jansky Very Large Array, a group of 27 radio telescopes in New Mexico, and the 21-telescope European VLBI Network. Together, these networks can achieve much higher resolution than any single radio dish. After observing nine more bursts, they located the FRB about 100,000 times more precisely than previous attempts with individual telescopes. This boost in precision allowed Chatterjee and his colleagues to unambiguously associate an FRB with other signals for the first time. Persistent radio waves that the researchers discovered originating from near FRB 121102 are actually coming from exactly the same place, an extremely faint dot in the sky. That tiny dot, FRB 121102’s home, is a dwarf galaxy. It’s around a tenth the diameter of the Milky Way, dim but still forming stars, and more than 2.5 billion light years away. “Before this step was taken, we could still continue having endless arguments about exactly how far away the FRBs were and therefore what their energetics were and what they were coming from,” says Chatterjee. “Now we know.” Knowing where an FRB comes from allows us to rule out some of the many proposed explanations for their origins. Since this example is so far away, it must be extremely energetic and bright – so it’s unlikely that any of the other FRBs we’ve seen come from our immediate neighbourhood. Two explanations for FRB 121102’s origin still stand out. The first is that it could come from an active galactic nucleus: a bright region around a black hole in the centres of some galaxies that spews radio waves as it vaporises the gas and plasma around it. But the researchers’ preferred explanation is that FRB 121102 and its constant radio companion are caused by the remnants of a supernova being energised by a young, rapidly spinning neutron star. Since the FRB’s host galaxy is similar to the surprisingly faint galaxies that produce the brightest supernovae, this scenario is an enticing fit – although it’s nowhere near proven yet. “What we learn from these papers may not be applicable to FRBs more broadly,” says Peter Williams at the Harvard-Smithsonian Center for Astrophysics. It is possible that FRB 121102 is special and that most FRBs are of an entirely different, non-repeating type. “However, folks have looked for interesting objects at the positions of other FRBs and nothing particularly compelling has turned up. That’s consistent with the fairly wimpy host galaxy revealed by this work.” Chatterjee shares that concern. “Our highest priority for the future is to find one more FRB that repeats,” he says. “Right now we are arguing from a sample of one, which is always a dangerous argument to be making.”

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