One scientist thinks a mysterious cosmic radio signal that turns itself on and off hourly is leaving astronomers confused after picking up a strange signal emanating from the far reaches of the cosmos. First discovered using Australia’s ASKAP radio telescope, ASKAP J1935+2148 has experts scratching their heads as to why it seems to repeat almost every hour.
The pulsating signal, which bounces back to Earth every 53.8 minutes, passes through three distinct phases:
1. Bright flashes lasting between ten and fifty seconds, with linear polarization where all radio waves “point” in the same direction.
2. Faint, short-lived pulses of only 370 milliseconds in duration and showing a circular polarisation.
3. Occasional silence, where the object misses its cue.
According to the lead researcher, Doctor Manisha Caleb, it was so different from all the rest: “What is intriguing is how this object displays three distinct emission states, each with properties entirely dissimilar from the others.” The MeerKAT radio telescope in South Africa enabled researchers to identify the three states and determine that the signals were emanating from the same source in the sky.
Scientists who discovered the mysterious signal believe that it is most likely emanating from a white dwarf or neutron star. Again, the characteristics of the signal are disproportionate to the present understanding of the physics of those celestial objects.
White dwarfs and neutron stars constitute the remains of more massive stars that have ended their life cycles. The final mass of the dying star is what dictates whether it will evolve as a neutron star or as a white dwarf. Neutron stars are known to pulse regularly with radio waves, thus earning the title of prime suspects for the mysterious signal. Agreements between very strong magnetic field configurations and complex plasma flows could lie at the root of the signal.
Although this signal was suspected to be created by a neutron star, considering its steadiness, the rotation period of 54 minutes is way beyond the rotation periods of neutron stars, which lie in seconds, even fractions of a second.
While a white dwarf could theoretically spin at such a slow pace, the discoverers behind the finding admit that “we don’t know of any way one could produce the radio signals we are seeing here.”
The observation of this confusing radio signal, ASKAP J1935+2148, is puzzling to astronomers because it goes against the current understanding of physics. This signal had some peculiar characteristics and followed an hourly cycle that produced more questions than answers in scientific circles. The scientific investigation that researchers undertook into this mystery of the cosmos reminds us that much of the universe remains unknown to this day and continues to give rise to new breaks in knowledge that change how we comprehend the cosmos.