Scientists Intrigued by Signal From Space Repeating Every Hour

A recent discovery of a repeating radio signal from deep space has captured the attention of scientists, leaving them both puzzled and intrigued. This signal, emanating from an object designated ASKAP J1935+2148, repeats every 54 minutes—a pace that challenges current astronomical understanding. The working hypothesis, as outlined in a study published in Nature Astronomy, suggests that the source might be a type of neutron star known as a pulsar. Pulsars are known for emitting regular bursts of radio waves as they spin on their axis. However, if ASKAP J1935+2148 is indeed a pulsar, it would be spinning much slower than any previously recorded neutron star, raising significant questions about the nature of these celestial objects.

Neutron stars are formed from the remnants of massive stars that explode in supernovae. The core left behind is incredibly dense, packing the mass of a star into an object only a few kilometers across. These stars possess powerful magnetic fields that emit streams of particles from their poles. As pulsars rotate, these streams create a pulsing signal observable from Earth. Typically, pulsars rotate within seconds; the fastest known spins 716 times per second. The extraordinarily slow rotation of ASKAP J1935+2148, completing a rotation every 54 minutes, contradicts existing models of neutron star behavior, suggesting it should be impossible for it to emit radio pulses at this rate.

Lead author Manisha Caleb from the University of Sydney Institute for Astronomy highlighted the anomaly of discovering a neutron star candidate emitting radio pulses at such an unusually slow pace. This discovery adds to a growing list of stellar remnants that defy current explanations.

ASKAP J1935+2148 exhibits three distinct emission states. The primary state features strong radio signals lasting between 10 to 50 seconds. In another state, it emits weaker pulses, 26 times fainter, that last a mere third of a second. The third state is quiescent, with no emissions. Over eight months of observation, researchers noted that the emission patterns evolved, indicating potential physical changes in the emitting region.

Given the anomalies, the researchers also consider the possibility that ASKAP J1935+2148 could be a highly magnetized white dwarf, the most common type of stellar remnant. However, this hypothesis also faces challenges. If such highly magnetized white dwarfs exist, they should be detectable due to their powerful emissions, yet none have been observed so far.

The discovery of ASKAP J1935+2148 and its unusual properties may prompt astronomers to revisit and potentially revise their long-standing theories about neutron stars and white dwarfs, particularly regarding how these objects emit radio waves and their distribution in the Milky Way galaxy. Further investigation is needed to understand this mysterious object fully and its implications for astrophysics.