White dwarf binary discovered only 150 light years away is a major supernova candidate in about 23 billion years
Astronomers have discovered only 150 light years away the most massive white dwarf binary system yet detected, that they believe is a major candidate for producing one type of supernova many billions of years in the future.
White dwarf stars in binary systems are thought to produce Type 1a supernova. The dwarf sucks material from the companion star, which eventually piles up on the surface of the dwarf until the extra mass, more than 1.4 times the mass of the Sun (dubbed the Chandrasekhar mass limit), causes the supernova explosion.
That’s the theory at least. Up to now astronomers have not yet observed this process, prior to the supernova. This newly discovered binary system however is a prime candidate, because its combined mass is already 1.55 the mass of the Sun. According to the researchers’ computer models, when these stars come close to merging the result will be a Type 1a supernova. From the peer reviewed paper:
The interaction of the accretion stream with the surface of the primary white dwarf ignites a helium detonation close to the point of interaction. The helium detonation then wraps around the primary white dwarf and sends a shock wave into its core that converges at a single point. This ignites a second detonation that completely destroys the primary white dwarf. When the shock wave of its explosion hits the secondary white dwarf, the double detonation mechanism repeats itself. The shock wave from the detonation of the primary ignites a helium detonation near the surface of the secondary which drives a shock wave into its core. It is sufficient to ignite the core detonation, destroying the secondary white dwarf as well.
These events won’t occur tomorrow however. The two stars orbit each other every 14 hours, but their high mass is causing gravitational waves to ripple outward from the system, robbing it of energy. The orbits of the stars are thus spiraling inward. In about 23 billion years they will be about to merge, which will be the moment when the above explosive events are predicted to occur.
If at that moment the binary system was still only 150 light years away, the explosion would do great harm to the Earth and likely cause a major extinction. In 23 billion years however the binary will no longer be so close, and could in fact be on the other side of the Milky Way.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Astronomers have discovered only 150 light years away the most massive white dwarf binary system yet detected, that they believe is a major candidate for producing one type of supernova many billions of years in the future.
White dwarf stars in binary systems are thought to produce Type 1a supernova. The dwarf sucks material from the companion star, which eventually piles up on the surface of the dwarf until the extra mass, more than 1.4 times the mass of the Sun (dubbed the Chandrasekhar mass limit), causes the supernova explosion.
That’s the theory at least. Up to now astronomers have not yet observed this process, prior to the supernova. This newly discovered binary system however is a prime candidate, because its combined mass is already 1.55 the mass of the Sun. According to the researchers’ computer models, when these stars come close to merging the result will be a Type 1a supernova. From the peer reviewed paper:
The interaction of the accretion stream with the surface of the primary white dwarf ignites a helium detonation close to the point of interaction. The helium detonation then wraps around the primary white dwarf and sends a shock wave into its core that converges at a single point. This ignites a second detonation that completely destroys the primary white dwarf. When the shock wave of its explosion hits the secondary white dwarf, the double detonation mechanism repeats itself. The shock wave from the detonation of the primary ignites a helium detonation near the surface of the secondary which drives a shock wave into its core. It is sufficient to ignite the core detonation, destroying the secondary white dwarf as well.
These events won’t occur tomorrow however. The two stars orbit each other every 14 hours, but their high mass is causing gravitational waves to ripple outward from the system, robbing it of energy. The orbits of the stars are thus spiraling inward. In about 23 billion years they will be about to merge, which will be the moment when the above explosive events are predicted to occur.
If at that moment the binary system was still only 150 light years away, the explosion would do great harm to the Earth and likely cause a major extinction. In 23 billion years however the binary will no longer be so close, and could in fact be on the other side of the Milky Way.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
“The helium detonation then wraps around the primary white dwarf and sends a shock wave into its core that converges at a single point.”
I have a lot more respect for helium, now.
And I believe that Sol (our star) will have gone red giant about 18 billons years before that. Per whatever the Brave AI distills from, in about 1 billon years Earth will have been “cooked” by an increasingly hot sun.
About 25 billion years!
Can’t wait!
I’m not holding my breath
And the (actual) global warming – from our Sun – will make this planet uninhabitable in maybe one billion years, by which point we will not be within 150 ly of this binary.