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Astronomers uncover a tremendous cosmic object unlike any they've ever seen before.

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.Astronomers have discovered a mysterious, flickering object in the Milky Way that emits massive amounts of energy toward Earth three times every hour.


This extraordinarily powerful object, located approximately 4,000 light-years from the sun, is unlike any cosmic structure yet discovered, according to researchers in a paper published in the journal Nature on Jan. 26.


The object in issue, GLEAM-X J162759.5-523504.3 (but let's just call it GLEAM for short), emerged out of nowhere during a recent radio wave study of the Milky Way. GLEAM, according to the researchers, flared dramatically over around 60 seconds, briefly becoming one of the brightest things in the entire sky, then vanished into the darkness. The object reappeared around 20 minutes later, slowly lighting to peak brightness before dimming back to nothing a minute later.


Transients are objects that emerge and disappear in front of our telescope lenses. Transients are often either a dying star (a supernova) or the strange, fast-spinning corpse of an already-dead star (a neutron star). However, neither of those usual explanations fit the behaviour of this newfound entity, according to the researchers in the new study.


The mystery GLEAM may be evidence of a previously unknown sort of star object — or possibly one that astronomers haven't ever imagined.


"During our observations, this object appeared and vanished over a few hours. That was entirely unexpected "Natasha Hurley-Walker, principal study author and radio astronomer at Curtin University in Bentley, Australia, said in a release. "It was kind of eerie for an astronomer because nothing known in the sky did that."


The last rays of a dying star

Transients are classified into two types. "Slow transients" can appear for a few days and then vanish after a few months. Supernovas, for example, flare brilliantly as dying stars eject their outer atmospheres in massive explosions, then gradually dim as the stellar leftovers cool.


Then there are "rapid transients," which appear and disappear every few milliseconds. Pulsars are neutron stars that revolve extremely quickly while emitting intense radio emissions caused by the magnetic field of a dead star.


The new study's authors were looking for transients like these using the Murchison Widefield Array (MWA) radio telescope in Australia's outback when they discovered GLEAM. The on-off blinking is too fast for a supernova and too sluggish for a pulsar; the one-minute-long brightening pattern of GLEAM defies explanation, according to the researchers.


An examination of the item revealed that it was extremely bright yet much smaller than the sun. According to the study's authors, GLEAM's radio emissions were also highly polarised (that is, their light waves only vibrated on a single plane), implying that they were generated by an incredibly powerful magnetic field.


These properties are similar to those of a speculative phenomenon known as an "ultra-long period magnetar," which is essentially a strongly magnetic neutron star that rotates extremely slowly. This unique class of item, while anticipated to exist, has never been spotted in space previously, according to the researchers.


"Nobody expected to directly detect one like this since they weren't thought to be so brilliant," Hurley-Walker explained. "It converts magnetic energy to radio waves considerably more efficiently than anything we've seen before."


The researchers stated that there could be alternative reasons for the enigmatic GLEAM. It could be a unique sort of white dwarf star (the shrivelled husk of a dead star that isn't large enough to collapse into a neutron star) that emits radio waves by sucking in material from a binary companion star. The scientists speculated that if such a star revolved at just the appropriate speed, it may appear to pulse like GLEAM.


To solve this star riddle, more measurements in other areas of the electromagnetic spectrum are required. Now that GLEAM has been discovered, the researchers are looking through archival observations from the MWA to determine whether any comparable objects have ever been discovered.

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