The star known as Betelgeuse used to be one of the brightest objects in our night sky. In fact, it was easily discernible to the naked eye, gleaming brightly from the shoulder of the constellation Orion.
And that’s to be expected from a star that’s not only relatively close to us, but also classified as a red supergiant, puffing up about 700 times as wide as our own sun.
But lately something has been eating Betelgeuse. According to a newly published paper from researchers at Pennsylvania’s Villanova University, the star has turned down the lights dramatically in the last two months. Scientists say it’s about 2.5 times fainter than its usual brilliant self — going from the ninth brightest object in the sky to the 23rd.
As a variable star, Betelgeuse waxes and wanes in brightness as part of a natural cycle. But it’s losing its shine so fast, astronomers suspect it may be primed to go supernova.
When a star comes to an end, it often dims before unleashing a luminosity that’s exponentially greater than usual. Supergiants don’t typically die boring deaths.
And if Betelgeuse does explode, its proximity to Earth would make it a blinding beacon in the sky, day or night.
“I personally think it’s going to bounce back, but it’s fun to watch stars change,” lead study author Ed Guinan tells CNN. Although, he adds, if Betelgeuse keeps losing its shine, “all bets are off.”
Our sun barely registers as a pinprick compared to Betelgeuse. (Photo: Aliona Ursu/Shutterstock)
Guinan, who has been observing Betelgeuse for decades, says the star’s distance from us makes an accurate diagnosis impossible.
“What causes the supernova is deep inside the star,” Guinan adds.
The thing is, since it’s 700 light-years from Earth, Betelgeuse may have already issued its last sigh. That’s because the news of its demise would take 700 years to reach us. But if its sudden dimming does suggest the red giant is going the way of the supernova, Earthlings still get treated to a spectacular light show — even if it’s not exactly a “live” event.
What’s more, the shock wave, radiation and celestial debris from Betelgeuse’s passing wouldn’t reach our solar system’s doorstep for about 6 million years, according to National Geographic. And our ever-protective sun would hold up an umbrella, to make sure Earth doesn’t get rained with star innards — leaving humans to bask safely in the cosmic pyrotechnics.
“It would be so incredibly cool!” astronomer Sarafina Nance, who was not involved with the research, tells National Geographic. “By far and away the most incredible thing to happen in my life.”
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What’s eating Betelgeuse?
Betelgeuse is dimming so fast, astronomers say it may be primed to explode.
