fast radio bursts

Mysterious repeating radio signals from outside our galaxy discovered

Astronomers recently discovered a strange repeating rhythm of fast radio bursts coming from outside our galaxy. The radio bursts come from 500 million light-years away, according to a statement released by MIT, which participated in the research. A light-year, which measures distance in space, equals about 6 trillion miles. Details of the radio bursts emerged earlier this year. The research has now been published in the journal Nature. “Fast radio bursts, or FRBs, are short, intense flashes of radio waves that are thought to be the product of small, distant, extremely dense objects, though exactly what those objects might be is a longstanding mystery in astrophysics,” the researchers explained in the statement. “FRBs typically last a few milliseconds, during which time they can outshine entire galaxies.” The fast radio burst source has been cataloged as FRB 180916.J0158+65. Experts say that it is the first to produce a periodic, or cyclical, pattern of bursts. “The pattern begins with a noisy, four-day window, during which the source emits random bursts of radio waves, followed by a 12-day period of radio silence,” the researchers said. The 16-day pattern appeared consistently over a 500-day period. “This FRB we’re reporting now is like clockwork,” said Kiyoshi Masui, assistant professor of physics in MIT’s Kavli Institute for Astrophysics and Space Research, in the statement. “It’s the most definitive pattern we’ve seen from one of these sources. And it’s a big clue that we can use to start hunting down the physics of what’s causing these bright flashes, which nobody really understands.” Usually, fast radio bursts are “one-offs,” according to experts, although in some cases they have come from the same source. The Canadian Hydrogen Intensity Mapping Experiment (CHIME) radio telescope in British Columbia was the first to pick up the signals from FRB 180916.J0158+65. The telescope picked up 38 signals from the source between September 2018 and February 2020. Astronomers say that they traced the signal to a star-churning region on the outskirts of a massive spiral galaxy. Spiral galaxies, like our Milky Way, have a central nucleus and “spiral arms” containing stars, gas and cosmic dust. “These periodic bursts are something that we’ve never seen before, and it’s a new phenomenon in astrophysics,” said Masui in the statement. In a paper published in the journal Nature, the scientists discuss the possible scenarios that created the radio bursts. “One possibility is that the periodic bursts may be coming from a single compact object, such as a neutron star, that is both spinning and wobbling — an astrophysical phenomenon known as precession,” they explained in the statement. “Another possibility involves a binary system, such as a neutron star orbiting another neutron star or black hole.” A third scenario involves a radio-emitting star orbiting a central source. “If the star emits a wind or cloud of gas, then every time the source passes through the cloud, the gas from the cloud could periodically magnify the source’s radio emissions,” the scientists explain. One possibility is that the fast radio bursts come from magnetars — neutron stars that are thought to possess a powerful magnetic field. Masui is part of the CHIME/FRB Collaboration, which also includes experts from the University of British Columbia, McGill University, the University of Toronto and the National Research Council of Canada. In a separate project, scientists used the Lovell telescope in the U.K. to discover a fast radio burst from deep space that has a 157-day repeating pattern. FRB 121102 shows activity for 90 days and then goes silent for 67 days, according to a study that was recently published in the Monthly Notices of the Royal Astronomical Society.

Things that make ya’ go, “hmm.”  For more, click on the text above.       🙂

Strange radio bursts from space come in clusters: study

Mysterious and powerful radio waves from deep space are coming in clusters, scientists revealed on Wednesday, having only discovered their existence a decade ago. The repeated pulses emanate from well beyond the edge of the Milky Way Galaxy, according to a study published in the journal Nature. It was previously thought that these so-called fast radio bursts (FRBs) — which can emit as much energy in a millisecond as the Sun emits in 10,000 years — were one-off phenomena. Less than 20 have been detected since 2007, though more than 10,000 are suspected to occur every day. Their origins remain unknown. Up to now, astronomers speculated that they were produced by cataclysmic events such as stars exploding into a supernovas, or neutron stars collapsing into black holes. But none of these scenarios are consistent with multiple pulses, leaving scientists at a loss as to how to interpret the new data. Peter Scholz, a graduate student at the McGill Space Institute at McGill University in Montreal and a co-author of the paper, discovered evidence of the bursts in November while sifting through data gathered by the Arecibo telescope in Puerto Rico. “I knew immediately that the discovery would be extremely important in the study of FRBs,” Scholz said in a statement. The telescope, the largest of its kind, had picked up a total of 10 radio wave pulses, all grouped within the space of a minute. “Not only did these bursts repeat, but their brightness and spectra also differ from those of other FRBs,” said Laura Spitler, lead author and a researcher at the Max Planck Institute for Radio Astronomy in Bonn, Germany. The latest findings appear to be at odds with research published only last week in Nature that concluded that FRBs are generated by one-off cataclysms. But it is now thought that there could be two or more sources for frequent radio bursts. The researchers speculated that multiple pulses could come from an “exotic object” such as a hugely powerful, rotating neutron star. Locating the galaxy from which the serial burst came would be “critical to understanding its properties,” said Jason Hessels, a co-author of the study and a professor at the University of Amsterdam. Pinpointing the source could also tell astronomers how long it took for the waves to reach Earth, a voyage likely measured in billions of light years. Comparing theoretical travel time in a vacuum with actual travel time could shed light on the distribution of matter in the universe.

Things that make ya go, “hmmm…”   And, sounds like these scientists are just pulling theories out of their collective butts..