The skies have been pretty exciting so far this year over southern Canada with April’s spectacular solar eclipse and May’s rare Northern Lights display. And now the future sometime this summer could be an exploding star visible to the naked eye.
“This could be a once-in-a-lifetime viewing opportunity as a nova explosion only happens every 80 years,” according to this NASA blog.
The blog explains that T Coronae Borealis, or T CRB, which is in a star system in our own Milky Way galaxy about 3,000 light-years from Earth, last exploded in 1946 and that astronomers believe it will do so again sometime before September 2024.
That stellar explosion, of course, would be nothing compared to another much closer, much larger star to earth that some think is primed not only for nova, but also for supernova — Betelguese.
Now to keep that in perspective, astronomers are much more certain about the time frame of T Coronae Borealis’ imminent explosion than Betelguese could be tomorrow, or (tens of) thousands of years from now.
T Coronae Borealis, said Elaina Hyde, assistant professor in the department of physics and astronomy at York University and director of the Allan I. Carswell Observatory in Toronto, “is a pretty interesting star. We’re actually looking at it in our observatory right now just to see what happens.”
The observatory, she said, “has a student-run crew and a 1-metre telescope, which is the largest telescope on a Canadian campus, so by observing it every night for a few hours we can hopefully get lucky; hopefully we Will be able to capture a part of that light curve (when it explodes).
It’s nicknamed the “flaming star,” she said, adding that “it’s actually what’s called a nova, which is when two stars orbit each other and one of them collects material and explodes periodically.”
The two stars are a red giant and a white dwarf, she explained, with the dense white dwarf essentially being pulled by the bloated red star.
And once in a while — or to be more specific every 80 years — it “reaches a flash point and explodes in a runaway thermonuclear explosion,” according to this NASA primer.
The original white dwarf actually survives the explosion to start collecting material from the red giant – and explodes again!
Our own sun is destined to go through the red giant and white dwarf phases, Hyde explained — but not until about 5 billion years from now, when it has melted all of its regular hydrogen fuel into the core. his, according to this primer in the life cycle. of the sun from space.com.
Betelguese, on the other hand, is an entirely different type of star headed for a different kind of explosion – a supernova.
It’s not just a red giant, but a red supergiant, so if it were in our solar system it would envelop all the planets up to Jupiter – according to this NASA explanation.
Unlike the much smaller sun, which essentially cannot fuse anything after using up all its hydrogen and then helium, supergiants can continue to fuse heavier and heavier elements “into carbon with oxygen with calcium and eventually to iron. ” according to this NASA explainer.
But that’s where the party stops. Iron simply does not melt. And so there’s basically nothing to stop the massive star from simply collapsing in on itself only to violently recoil in an explosion that can briefly burn brighter than the entire galaxy it’s in, according to this NASA primer -s above the big stars.
And when it does blow, scientists expect its brightness could match that of a crescent moon with a full moon briefly in our night sky.
It is already among the brightest stars in our night sky, according to this NASA article, as it is both large and relatively close at about 450 light years.
The star has been in the news in recent years after an unusual dimming event left some experts wondering if it was about to blow up, but the consensus is that scientists simply don’t know exactly what stage it is in and so can’t predict. its demise for sure – but probably not soon.
T CRB, on the other hand, is not visible to the naked eye, and when it goes nova, its brightness, according to Hyde, will increase for a time slightly lower than Betelguese’s brightness now.
“You have to look for it in pretty dark skies,” she said, adding that the real thrill would be that it’s “something new that we might suddenly see.”