Space is full of extreme phenomena, but the \u201cTasmanian devil\u201d may be one of the weirdest and rarest cosmic events ever observed. <\/p>\n
Months after astronomers witnessed the explosion of a distant star, they spotted something they have never seen before: energetic signs of life releasing from the stellar corpse about 1 billion light-years from Earth. The short, bright flares were just as powerful as the original event that caused the star\u2019s death. <\/p>\n
Astronomers dubbed the celestial object the \u201cTasmanian devil,\u201d and they observed it exploding repeatedly following its initial detection in September 2022. <\/p>\n
But the initial stellar explosion that caused the star\u2019s death wasn\u2019t any typical supernova, an increasingly bright star that explodes and ejects most of its mass before dying. Instead, it was a rare type of explosion called a luminous fast blue optical transient, or LFBOT. <\/p>\n
LFBOTs shine brightly in blue light, reaching the peak of their brightness and fading within days, while supernovas can take weeks or months to dim. The first LFBOT was discovered in 2018, and astronomers have been trying to determine the cause of the rare cataclysmic events since. <\/p>\n
But the Tasmanian devil is revealing more questions than answers with its unexpected behavior. <\/p>\n
While LFBOTs are unusual events, the Tasmanian devil is even stranger, causing astronomers to question the processes behind the repetitive explosions. <\/p>\n
\u201cAmazingly, instead of fading steadily as one would expect, the source briefly brightened again \u2014 and again, and again,\u201d said lead study author Anna Y.Q. Ho, assistant professor of astronomy in Cornell University\u2019s College of Arts and Sciences, in a statement. \u201cLFBOTs are already a kind of weird, exotic event, so this was even weirder.\u201d <\/p>\n
The findings about the latest Tasmanian devil LFBOT discovery, officially labeled AT2022tsd and observed with 15 telescopes around the globe, published Wednesday in the journal Nature. <\/p>\n
\u201c(LFBOTs) emit more energy than an entire galaxy of hundreds of billions of stars like the Sun. The mechanism behind this massive amount of energy is currently unknown,\u201d said study coauthor Jeff Cooke, a professor at Australia\u2019s Swinburne University of Technology and the ARC Centre of Excellence for Gravitational Wave Discovery, in a statement. \u201cBut in this case, after the initial burst and fade, the extreme explosions just kept happening, occurring very fast \u2014 over minutes, rather than weeks to months, as is the case for supernovae.\u201d <\/p>\n
Software written by Ho initially flagged the event. The software sifts through a half-million transients detected daily by the Zwicky Transient Facility in California, which surveys the night sky. Ho and her collaborators at different institutions continued to monitor the explosion as it faded and reviewed the observations a few months later. The images showed intense bright spikes of light that soon vanished. <\/p>\n
\u201cNo one really knew what to say,\u201d Ho said. \u201cWe had never seen anything like that before \u2014 something so fast, and the brightness as strong as the original explosion months later \u2014 in any supernova or FBOT (fast blue optical transient).
We\u2019d never seen that, period, in astronomy.\u201d <\/p>\n
To better understand the quick luminosity changes occurring in the Tasmanian devil, Ho and her colleagues reached out to other researchers to compare observations from multiple telescopes. <\/p>\n
Altogether, the 15 observatories, including the high-speed camera ULTRASPEC mounted on the 2.4-meter Thai National Telescope, tracked 14 irregular light pulses over 120 days, which is likely just a fraction of the total number of flares released by the LFBOT, Ho said. <\/p>\n
Some of the flares only lasted tens of seconds, which to astronomers suggests that the underlying cause is a stellar remnant formed by the initial explosion \u2014 either a dense neutron star or a black hole. <\/p>\n
\u201cThis settles years of debate about what powers this type of explosion, and reveals an unusually direct method of studying the activity of stellar corpses,\u201d Ho said. <\/p>\n
Either object is likely taking on large amounts of matter, which fuels the subsequent bursts. <\/p>\n
\u201cIt pushes the limits of physics because of its extreme energy production, but also because of the short duration bursts,\u201d Cooke said. \u201cLight travels at a finite speed. As such, how fast a source can burst and fade away limits the size of a source, meaning that all this energy is being generated from a relatively small source.\u201d <\/p>\n
If it\u2019s a black hole, the celestial object may be ejecting jets of material and launching them across space at near the speed of light. <\/p>\n
Another possibility is that the initial explosion was triggered by an unconventional event, such as a star merging with a black hole, which could present \u201ca completely different channel for cosmic cataclysms,\u201d Ho said. <\/p>\n
Studying LFBOTs could reveal more about the afterlife of a star, rather than just its life cycle that ends with an explosion and a remnant. <\/p>\n
\u201cBecause the corpse is not just sitting there, it\u2019s active and doing things that we can detect,\u201d Ho said. \u201cWe think these flares could be coming from one of these newly formed corpses, which gives us a way to study their properties when they\u2019ve just been formed.\u201d <\/p>\n
Astronomers will keep surveying the sky for LFBOTs to see how common they are and uncover more of their secrets. <\/p>\n
\u201cThis discovery teaches us more about the varied ways in which stars end their lives and the exotica that inhabit our Universe,\u201d said study coauthor Vik Dhillon, professor in the department of physics and astronomy at the University of Sheffield in the United Kingdom, in a statement. <\/p>\n\n
Space is full of extreme phenomena, but the \u201cTasmanian devil\u201d may be one of the weirdest and rarest cosmic events ever observed. Months after astronomers witnessed the explosion of a distant star, they spotted something they have never seen before: energetic signs of life releasing from the stellar corpse about 1 billion light-years from Earth. <\/p>\n","protected":false},"author":0,"featured_media":11724,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[],"class_list":{"0":"post-11723","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-world"},"_links":{"self":[{"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/posts\/11723","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/comments?post=11723"}],"version-history":[{"count":0,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/posts\/11723\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/media\/11724"}],"wp:attachment":[{"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/media?parent=11723"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/categories?post=11723"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/shareperformanceinsight.com\/index.php\/wp-json\/wp\/v2\/tags?post=11723"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}