Astronomers have discovered 20 mysterious radio signals from outer space

Astronomers have discovered 20 mysterious radio signals from outer space

32
0
SHARE

A large number of fast radiuspacket (FRB), discovered by Australian scientists can help astronomers to finally understand the mysterious nature and find out the source of these powerful radio pulses from deep space. The article of the journal Nature, published October 10, reported on the opening of 19 new FRB signals. One of their sources, as researchers found, was closest to Earth among all the previously recorded FRB. Another signal was the brightest ever recorded. Since first opening in 2007, it was discovered only 34 such a signal, so a new discovery significantly increases their total number.

Fast radio bursts (fast radio bursts, FRB) are very fast (lasting only a few milliseconds), but it is tremendously powerful radioliberty containing amounts of energy, equivalent to the amount of energy produced by our Sun for almost a century. Previously, scientists have offered many hypotheses to explain their origin (supernovae, unique types of neutron stars, even aliens), but astronomers still do not know what is the source of such incredible power.

The new study was led by Ryan Shannon of the Australian Swinburne University of Technology. From the beginning of 2017, he and his team were in search of fast radio bursts, using a powerful radio ASCAP (Australian Square Kilometre Array Pathfinder, ASKAP, the Australian Ranger-square-kilometer grid), consisting of 36 antennas of diameter 12 meters. A systematic search which lasted more than a year have borne fruit – 20 discovered the new FRB. (About one of the signals, scientists reported earlier in another article, so technically the number of new signals is equal to 19).

The team’s success can be attributed to two aspects, says study co-author Keith Bannister from the State Association scientific and applied research (CSIRO), the Australian science Agency, have developed and built a radio interferometer ASCAP.

“The angle of the telescope is 30 square degrees, which is 100 times larger than the size of the full moon in the sky,” says Bannister.

“Through the use of the antennas of the telescope in a rather unusual way – when each was directed to a different point in the sky, we were able to obtain a viewing angle of 240 square degrees, which is already about 1000 times larger than the size of the full moon. ASCAP is ideal for such work”, — adds the scientist.


An artistic representation of one of the plates of the telescope ASCAP defining a quick burst. Scientists still don’t know what is the source of these incredibly powerful signals and their energy equal to the energy of the Sun, produced for 80 years

According to Shannon Ryan, the analysis of the signals shows that the fast radio bursts come to us from the other end of the Universe and not from our galactic neighbors. Scientists also found that among the 20 caught signal one source, called FRB 171020, should be located closest to the Earth, among all the others – is about 425 million light-years. It is almost twice closer than the putative homeland of the nearest previous signal, adds Shannon.

In addition, with the help of ASCAP managed to catch the most powerful FRB signal. Again, says Shannon, he was twice more powerful than the most powerful among the previous.

None of the signals during the observed period, scientists were not recorded again, although the team has repeatedly conducted monitoring for the approximate coordinates of each of the signals, which in total took more than 12 000 hours of operation.

By the way, to date, among all caught FRB signals only one was “repeated”. Source FRB 121102 scientists several times since its discovery in 2012, the recorded bursts. Moreover, one August day in 2017, this source made a real attack – 93 (!) recorded burst.

A unique example of FRB 121102, as well as new results of the Australian team of scientists down to the very important issue, says Shannon: “How many types of FRB signals exist? Since differences between duplicate source and other is becoming increasingly difficult to ignore.”

Another feature of the new detected signals, says the scientist, is their low variance — the discrepancy between the various wavelengths that make up the surge. Usually this indicator shows how often the signals had to overcome the different environments that they have slowed down.

“The fact of the existence of a relationship between the brightness and dispersion tells us that matter who were in the path of these signals, is outside of galaxies, clusters of rarefied gas in the intergalactic medium. In other words, thanks to FRB-signals, we can find out what is the matter. When using other methods of observations (optical, x-ray and so on) it is almost impossible to do,” explains Shannon.

In the future, Shannon and his colleagues really want to narrow it down to the source of the FRB signals. Scientists believe that they can at least figure out some of the galaxies came from these signals.

To discuss the opening of the astronomers and to propose his hypothesis of the origin of the FRB signals is possible in our Telegram chat.