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2021-2022: XLII

"In all chaos there is a cosmos, in all disorder, a secret order."

-Carl Jung

THE DAILY ASTRONOMER

Tuesday, November 16, 2021

Strange Galactic Signals

Astronomers are perplexed. That confusion is hardly unusual. Throughout history, astronomers have often been perplexed, hence the advent of astronomy, the study of a perplexing Universe. This time, the confusion has arisen over a series of strange signals emanating from the galactic center.

Located nearly 27,000 light years from the solar system, the galactic center is a furiously energetic region in which millions of densely packed stars whip around a supermassive black hole that is about four million times more massive than the Sun.        

As this nucleus is so energetic, it produces copious amounts of energy all along the electromagnetic spectrum.  It is not that emission of signals that is causing brows to furrow, but the nature of these particular signals.        First,they are quite random: appearing for weeks at a time and then snapping off within the space of a single day, a stunningly rapid transition for astronomical objects.   Secondly, the intensity fluctuates dramatically, at one point it intensified to 100 times the radio brightness of its previous output.   

This source, named  ASKAP J173608.2-321635 (a reference to its coordinates relative to the galactic center), exhibits behaviors inconsistent with any known celestial objects, including pulsars.  Pulsars are rapidly rotating neutron stars produced by supernovae, the explosions that end the lives of highly massive stars.     Pulsars emit two lobes of radio energy, hence their name as these lobes seem to "pulse" as they sweep by an observer.          Yet, they are periodic, predictable and the energy emission remains consistent.   

ASKAP J173608.2-321635 's signals are unlike anything astronomers have yet observed.    While they are highly reluctant to ascribe these emissions to extraterrestrial intelligence,*  they do believe these signals might originate from a new type of stellar object not yet identified.

Astronomers will continue to monitor this region for further signals, in the hope that subsequent observations will lend more insight into its nature.   As for now, something deeply mysterious is casting signals from the maelstrom of the galactic center and we'll have to wait to find out if it is something not yet known.     The perplexity continues.  

*Understand that radio astronomers are still crestfallen due to  a profoundly disappointing "false signal" once believed to have come from Proxima Centauri, the closest star system to the Sun.     This latest "wow" signal, thought perhaps to have been produced by "next door aliens," was instead emitted by a land-based object in Australia.     Another dashed hope.

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