A star 1,540 times larger than the Sun is mutating in real time and it is something that baffles astronomers
The universe is rarely in a hurry, since stellar processes usually be measured in millions or billions of yearsso witnessing the metamorphosis of a great star in the span of a single human life is practically unheard of. And this is precisely what is happening with WOH G64a true cosmic monster located in the Large Magellanic Cloudabout 163,000 light years from Earth. Big changes. Astronomers have been analyzing this astronomical giant for years, and now the red supergiant is changing radically in front of our telescopes as it heats up rapidly and opens a heated scientific debate. The question that the community is asking itself right now is whether we are facing the transformation towards a very rare yellow hypergiant or if it is simply the fierce interaction of a binary system before collapsing. What we knew. Discovered in the 1970s, WOH G64 has long held the title of one of the largest stars known. The data we know about it is no wonder, since it has a radius 1,540 times greater than that of our Sun, an approximate mass of 28 solar masses and shines 282,000 times brighter than our star. Despite its enormous size, it is an extremely young star, since it is barely 5 million years old. And if we put it into context, in the ruthless world of astrophysics, the largest stars “live fast and die young”, devouring the fuel inside them at great speed. The script twist. Until recently, everything fit the classic profile of an extreme red supergiant, placing its temperature at 3,400 ± 25 degrees Kelvin. But a turning point came in the last decade after the data published in Nature Asia which pointed out that the star suffered a mysterious dimming in 2011, followed by a sudden warming of more than 1,000 ºC and significant chemical alterations in the atmosphere. Now, a new study analyzes the photometry and optical spectroscopy accumulated over more than thirty years of this star. And the conclusion they have reached is that between 2013 and 2014, WOH G64 began to transition from red supergiant to yellow hypergiant. What are they? Yellow hypergiants are an exceptionally rare transition phase of which we barely have data and, above all, it is very ephemeral. In this case, the dramatic thermal evolution could be due to the star having partially ejected its outer envelope or to its stellar companion aggressively stripping away material. The debate is served. As is often the case on the frontier of astrophysics, not everyone agrees that the transition is complete. Rigorous science requires fact-checking constant, and recent research adds nuance to this story. This same year, one study pointed out because the star continues to maintain its classic red supergiant characteristics, questioning whether it has become a rare yellow hypergiant. The most logical explanation they see in this case is that the interaction with its companion star is causing these large temperature changes. This generates a great debate, since it goes completely against the other part of astrophysics that is convinced that we are facing a great twist in the script. A supernova. The big question that everyone is asking is how this titan will end, and some voices suggest that we are seeing the prelude to an imminent supernova. However, in astronomical terms, “imminent” is an elastic concept, since core collapse could occur in a time frame ranging from 100 to a few thousand years. And even if it collapses, even a spectacular explosion is not guaranteed. Although there is also the possibility that it fails in its attempt to explode and, instead, collapses directly in on itself, silently forming a black hole. Likewise, what happens seems to be something that our next generations will see. Images | European Southern Observatory In Xataka | We have analyzed the universe for 20 years looking for ET and all we have are 100 signals that China is now investigating
