“The strangest feature of this new signal is that it has a very high polarization,” said Ziteng Wang, lead author of the new study and a doctoral student at the Faculty of Physics, University of Sydney. But that’s not all, “the brightness of the object also changes dramatically, up to a hundred times – and these changes are probably completely random. We have never seen anything like it, “the scientist added.
What could it be?
Many types of stars emit variable light throughout the electromagnetic spectrum. Thanks to the tremendous advances in radio astronomy, science already knows enough about similar objects: they can be pulsars, supernovae, or fast radio flashes.
But the new discovery does not fit into any of these boxes. “At first we thought it might be a pulsar. But the signals from this source do not match the data we expect from these types of celestial objects, “said Wang, whose team’s observation results published in the Astrophysical Journal.
Under his leadership, scientists found a strangely flashing signal using the ASKAP CSIRO radio telescope in Western Australia, then verified it by observing the MeerKAT telescope in South Africa.
“Looking towards the center of the Galaxy, we found the object ASKAP J173608.2-321635, named after its coordinates. This object was unique in that it was initially invisible, then became clear, seemingly extinct, and then reappeared. This behavior was quite extraordinary, “said the authors of the research.
After astronomers detected six radio signals from this source in nine months in 2020, they tried to find the object in visual light. But they found nothing. They turned to the Parkes – radio telescope and again they could not detect the source.
“We found it to be a very interesting source,” astronomers said. “Then we tested the more sensitive MeerKAT radio telescope in South Africa. Because the signal was intermittent, we watched it every 15 weeks for 15 minutes, hoping to see it again. “
When the signal finally returned, they found that the behavior of its source had changed dramatically – the source disappeared in a single day, although it had taken weeks in previous observations on ASKAP. Perhaps most similar to this signal is the recently discovered class of cosmic objects called transient radio sources in the galactic center. Specifically, a subtype that earned the nickname “cosmic burper.”
But this resemblance is far from perfect; therefore, scientists want to study the remarkable behavior of cosmic oddity in the years to come. They hope for a new technical tool – the SKA (Square Kilometer Array) transcontinental radio telescope will be put into operation over the next decade. He will be so powerful that he could reveal the veil of mystery around ASKAP J173608.2-321635.