Defying explanation: Radio signals from outer space repeats every hour
A mysterious radio signal originating from space has baffled astronomers with its regular hourly repetitions, fluctuating through three distinct states. Despite their efforts, the signal's peculiar behavior defies explanation within the confines of current physics theories, adding to the enigmatic array of cosmic phenomena permeating the universe.
Detected within the vast expanse of data captured by the ASKAP radio telescope in Australia, the signal, formally known as ASKAP J1935+2148, manifests at intervals of approximately 53.8 minutes.
Intriguingly, this signal exhibits a cyclic pattern, transitioning through three distinct states. At times, it emits intense bursts, characterized by bright flashes lasting between 10 to 50 seconds, displaying a linear polarization indicative of radio waves aligned in a singular direction.
Conversely, in other instances, the signal presents weaker pulses lasting a mere 370 milliseconds, accompanied by circular polarization. Curiously, there are moments when the signal remains silent, failing to adhere to its expected cadence.
Dr. Manisha Caleb, the study's lead author, highlighted the puzzling behavior of the signal, noting, "What is intriguing is how this object displays three distinct emission states, each with properties entirely dissimilar from the others." She emphasized the critical contribution of the MeerKAT radio telescope in South Africa, stating, "If the signals didn’t arise from the same point in the sky, we would not have believed it to be the same object producing these different signals."
So, what might be the source of such an unusual radio signal? Let's address the elephant in the room first: it's unlikely to be aliens (probably). According to the scientists who unearthed it, the most plausible explanation is that it originates from either a neutron star or a white dwarf.
However, this explanation isn't straightforward, as the signal's peculiar characteristics defy our current understanding of the physics governing these celestial objects.
Neutron stars and white dwarfs, while sharing some similarities, also possess distinct characteristics. Both originate from the remnants of larger stars, with the initial mass determining whether a neutron star or a white dwarf forms.
Neutron stars are recognized for emitting regular bursts of radio waves, making them a plausible candidate for the source of this signal. It's conceivable that the signal's diverse nature could stem from interactions between their potent magnetic fields and intricate plasma dynamics. However, a significant hurdle arises: neutron stars typically rotate at speeds measured in seconds or fractions thereof per revolution. It appears implausible for one to spin as slowly as once every 54 minutes.
Conversely, white dwarfs could feasibly rotate at such a leisurely pace. Yet, as the research team notes, "we don’t know of any way one could produce the radio signals we are seeing here" from a white dwarf.
Indeed, the enigma surrounding repeating radio signals from space is not unprecedented. Several years ago, another perplexing signal was discovered, recurring at an 18-minute interval, a phenomenon deemed equally improbable. The emergence of this new signal, with its significantly extended duration and heightened complexity, only serves to deepen the mystery surrounding such cosmic occurrences.
"Exploring the true origin of the signal—whether it stems from an unconventional neutron star, a potential 'white dwarf pulsar,' or perhaps an entirely novel cosmic phenomenon—remains contingent upon further meticulous observation," Caleb emphasized. "This intriguing discovery may not only challenge but also compel us to reassess our long-standing comprehension of neutron stars and white dwarfs. We may need to reevaluate how these celestial objects emit radio waves and reconsider their distribution within our Milky Way galaxy."
