A quick, bright flash of radio waves from somewhere in space, known as a fast radio burst (FRB), has been detected as it was happening for the first time. Seven similar bursts have been detected since the first one was found in 2007. However, all of the previous phenomenon have been found by coming through data from the Parkes radio telescope in eastern Australia and the Arecibo telescope in Puerto Rico after the fact.
Isaac Asimov once said that “The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ but ‘That’s funny…’” and this is definitely one of those moments.
In the 1960s, Jocelyn Bell Burnell found a blip or a “scruff” on a radio array readout. It was a mystery at the time and Burnell’s team thought for a time that it might be an alien communication. In the end it turned out to be the first discovery of a pulsar, a find that resulted in a Nobel Prize for members of the research team.
Catching this event in real time may move researchers a step closer to solving the current mystery.
“These events are one of the biggest mysteries in the Universe. Until now, astronomers were not able to catch one of these events in the act,” said John Mulchaey, Carnegie Observatories’ Acting Director, in a statement.
As was the case with Burnell’s team in the 1960s, there are those who want to believe that it’s an alien message. That is somewhat understandable. When researchers talk about “fast radio bursts” there is are those who think that we picked up a clip of an alien Howard Stern Show or an audio greeting card.
“The search for extraterrestrial life (SETI) has long involved shouting at the cosmos with long-traveled radio messages, and then waiting for a response. It’s not utterly insane to at least consider that these FRBs could finally be a few responses,” said Brian Stallard of Nature World News in July, 2014.
However, in this case, there is substantial reason to believe that it’s not a response to SETI. According to data on this event gathered from 12 telescopes around the world the FRB originated 5.5 billion light years from Earth. That means that the event which caused the signal happened about 900 million years before our solar system began to form.
Even if it were found to be a communication from an intelligent alien species, by the time we could get a signal back to the source our sun would have burned out.
Fortunately there are a wide variety of other theories as to the sources of FRBs.
According to the Planetary Society, one possibility is that the signal came from a flaring star in our galaxy. This theory speculates that a radio signal passing through a “plasma blanket” created by the exploding star as it ejected layers of its atmosphere. Another possible explanation is that the FRB is caused by two binary white dwarf or neutron stars merging. Still another possibility is that it is the result of a “blitzar”. A blizzar is an intense burst of radio emissions caused when a supermassive neutron star collapses.
While the researchers behind the latest FRB discovery do not know what caused the burst, they have been able to rule some things out.
“Together, our observations allowed the team to rule out some of the previously proposed sources for the bursts, including nearby supernovae. Short gamma-ray bursts are still a possibility, as are distant magnetic neutron stars called magnetars, but not long gamma ray bursts,” explained Mansi Kasliwal of the Carnegie Institution.
Long gamma ray bursts can be caused by the energy released from a supernovae, these are followed by lower wavelength radiation called an “afterglow”. The team also believes, based on the polarization of the burst, that it originated near a magnetic field or passed through one which may help to locate the origin of the event.
“The theories are now that the radio wave burst might be linked to a very compact type of object — such as neutron stars or black holes — and the bursts could be connected to collisions or ‘star quakes.’ Now we know more about what we should be looking for,” Daniele Malesani from the University of Copenhagen in Denmark told Astronomy Magazine.
The latest findings on the real-time FRB discovery is published in the Monthly Notices of the Royal Astronomical Society.