--- title: "If Betelgeuse Explodes, It’ll Be So Bright You Could See It During the Day For a Year" description: "The erratic behavior of Betelgeuse, a bright star some 300 light years away, has many wondering what its supernova would look like." date: "2023-06-15" modified: "2023-06-17" authors: - name: "Frank Landymore" job_title: "Contributing Writer" link: "https://futurism.com/authors/flandymore" url: "https://futurism.com/the-byte/if-betelgeuse-explodes-bright" categories: - "Off-World" - "Space" tags: - "betelgeuse" - "stars" - "supernova" - "the digest" --- # If Betelgeuse Explodes, It’ll Be So Bright You Could See It During the Day For a Year ![The erratic behavior of Betelgeuse, a bright star some 300 light years away, has many wondering what its supernova would look like.]() *Betelgeuse is a red supergiant and the tenth-brightest star in the night sky. Taken at Natural park of Cabo de Gata. Almería. Andalusia. South of Spain. \Image: Getty Images\* ## Stellar Spectacle What happens when a nearby star explodes? That's been a pressing [question on]() [astronomers' minds]() for several months now, as the erratic behavior of Betelgeuse, which is only 500 light years away, has many wondering if it's primed to go supernova. Over the [past few years](), the red supergiant — already one of the brightest stars in the night sky — has gone from dimming dramatically between 2019 to 2020 to burning brighter than ever. Since April, Betelgeuse has beamed at over 150 percent [of its usual brightness](), at times outshining all the other stars in its constellation Orion. It's now been bumped to the seventh brightest star overall, up from number ten. Though it's not looking likely it'll detonate during our lifetimes, Albert Ziljstra, a professor of astrophysics at the University of Manchester, wants to explore what Betelgeuse's demise would look like from Earth anyway, because, well, why not? The short answer, according to a new [essay he penned for *The Conversation*](), is that it would be so resplendent that you could see it — or its imploded remnants, at least — during even the daylight, and for up to a whole year. ## Getting Litty To astronomers, the first indicator of Betelgeuse's destruction would actually be particles. "We first would detect a rain of massless particles called neutrinos, which would be harmless to us," Ailjstra writes. "After that, the star would quickly brighten." At that stage, Betelgeuse would become as luminous as the full Moon. It would then gradually fade from this peak, but remain visible in daylight for a lengthy six to twelve months. After sunset, though, is when the doomed star would really get to shine. "At night, you should be able to see it with the naked eye for another one or two years," Ailstra wrote — a pretty long time, in terms of explosions. "But after that, we would never see it again." ## Awesome, But Harmless Given its relative proximity, it's reasonable to wonder if Betelgeuse's end could be dangerous to life on Earth. Fortunately, Ziljstra says, there's little to worry about. The radiation brought by cosmic rays from a supernova at that distance "would be small compared to other radiation we receive for all but the nearest supernovas." One such supernova from some two to three million years ago was only 300 light years away, he notes, which irradiated iron as deep as the seabed but barely seemed to affect life on our planet. We would face some major problems at 30 light years away, though. At that distance, cosmic rays could dissipate our ozone and cause a mass extinction. That's extremely unlikely, however, happening "only once per billion years," according to Ziljstra. Still, while Ziljstra concludes that "Betelgeuse may still be around for some time," that hasn't stopped fellow astrophysicists from [expressing their desperate wishes to see it blow up](). And from how Ziljstra describes its spectacular aftermath, we can't blame them. **More on supernovae:** *[New Supernova in Sky May Shine for Months]()* ## Author At Futurism, my work has often centered on bringing a sense of clarity and insight to complex topics ranging from the regulation of emerging technologies to the esoteric ideologies of Silicon Valley executives, while striving not to lose the poetic sense of awe inspired by often-obscure fields like astrophysics and quantum computing. I broke the story of CNET using AI to produce articles that turned out to be riddled with factual errors and plagiarism — a dam-breaking inflection point, as I've reported, that's inspired copycats and endless discourse while beguiling stakeholders ranging from tech giants to purveyors of spam around the web. My work at Futurism has been cited by publications including CBS News, the Los Angeles Times, Vice, Gizmodo, Engadget, the Verge, and Vanity Fair. I grew up in locales ranging from India to China, and now live in the exotic suburbs of Virginia. In my free time, I'm an avid reader of weird sci-fi literature, an aficionado of East Asian cinema, and, regrettably, a relapsed gamer. Allegedly, I’m working on a debut novel, currently untitled. ### Author social links [Bluesky]()