Stars exploding as supernovae lose their mass to companion stars during their lives

Stars exploding as supernovae lose their mass to companion stars during their lives
A massive star evolving and becoming a red supergiant, and finally exploding as a supernova. A binary companion may strip the star's hydrogen away (producing supernova type IIb/Ib), and for a more massive star the stellar wind expels the remaining helium layer (producing supernova type Ic). Credit: Keiichi Maeda

Stars over eight times more massive than the sun end their lives in supernovae explosions. The composition of the star influences what happens during the explosion.

A considerable number of massive stars have a close companion star. Led by researchers at Kyoto University, a team of international researchers observed that some stars exploding as supernovae may release part of their layers to their before the explosion.

"In a binary star system, the star can interact with the companion during its evolution. When a massive star evolves, it swells to become a red supergiant star, and the presence of a companion star may disrupt the outer layers of this supergiant star, which is rich in hydrogen. Therefore, binary interaction may remove the hydrogen of the evolved star either partially or completely," says postdoctoral researcher Hanindyo Kuncarayakti from the Department of Physics and Astronomy at the University of Turku in Finland and the Finnish Centre for Astronomy with ESO. Kuncarayakti is a member of the researcher team that made the observations.

As the star has released a significant part of its hydrogen layer due to the close companion star, its explosion can be observed as a type Ib or IIb supernova. A more massive star explodes as a type Ic supernova after losing its helium layer due to the so-called . Stellar winds are massive streams of energetic particles from the surface of the star that may remove the helium layer below the hydrogen layer.

"However, the companion star does not have a significant role in what happens to the exploding star's helium layer. Instead, stellar winds play a key role in the process as their intensity is dependent on the star's own initial mass. According to and our observations, the effects of stellar winds on the of the exploding star are significant only for stars above a certain mass range," says Kuncarayakti.

The research group's observations show that the so-called hybrid mechanism is a potential model in describing the evolution of . The hybrid mechanism indicates that during its lifespan, the star may gradually lose part of its mass both to its companion star as a result of interaction as well as due to stellar winds.

"By observing dying as supernovae and the phenomena within, we can improve our understanding on massive star evolution. However, our understanding of massive star evolution is still far from complete," states Professor Seppo Mattila from the Department of Physics and Astronomy at the University of Turku.

Explore further

Image: Finding an elusive star behind a supernova

More information: Qiliang Fang et al, A hybrid envelope-stripping mechanism for massive stars from supernova nebular spectroscopy, Nature Astronomy (2019). DOI: 10.1038/s41550-019-0710-6
Journal information: Nature Astronomy

Citation: Stars exploding as supernovae lose their mass to companion stars during their lives (2019, March 8) retrieved 15 October 2019 from
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Mar 08, 2019
"In order to explode, stars firstly have to achieve very fast rotations around their respective axes and the arrival of a smaller object of an appropriate mass and structure, which would go deep inside a star and trigger the event that results with different ways of a star's destruction. Independently of their mass, red, orange and yellow stars don't produce Novaeā€¦
Very small quantity of events results with classical explosions of a total destruction. Many events have been recorded, in which a star rejects smaller or more significant part of its matter. In a part of an event (in a nebula), a star's core remains and it may become brighter (i.e., warmer), but also turn into a cold star of M type. These objects get detected after a star has exploded in the form of pulsars, "neutron" stars,. " https://www.ijsci...1908.pdf

Mar 08, 2019
I'm amazed that a companion star could survive a supenova.

Mar 09, 2019
Planets probably survive a supernova, although without much of an atmosphere and with some weird nuclear fallout on the surface...

Mar 09, 2019
Planets probably survive a supernova

I'm reminded of this quote form xkcd

...The physicist who mentioned this problem to me told me his rule of thumb for estimating supernova-related numbers: However big you think supernovae are, they're bigger than that

Which of the following would be brighter, in terms of the amount of energy delivered to your retina:

1) A supernova, seen from as far away as the Sun is from the Earth, or

2) The detonation of a hydrogen bomb pressed against your eyeball?

Applying the physicist rule of thumb suggests that the supernova is brighter.
And indeed, it is ... BY NINE ORDERS OF MAGNITUDE.

Mar 09, 2019
So yeah...a planet like earth would survive in some form...and it would look like if a billion hydrogen bombs had exploded on every square inch.

(though at 1 AU the Earth would not have been present anymore because that is already inside the envelope of any original red giant star before it goes nova. Earth would have long since have melted and been incoroprated into the star's plasma as some tiny, tiny amount of the non-hydrogen/non-helium trace elements)

Mar 10, 2019
After a few million years in the outer shell of Sol gone Red Giant?
The Earth remanent would define "briquette".

After a Super-Nova, so close up & personal?
The Earth would define "clinker"

Mar 10, 2019
The Earth would define "clinker"

Probably not even that. Remember that the xkcd article just talks about the radiation. But when a sun goes nova it also flings out a lot of plasma.

While "plasma" may not sound much more than a "puff of gas" we're talking several hundred thousand Earth masses of it at an appreciable fraction of the speed of light. That's one helluva lot of kinetic energy that'll come our way righ after the initial radiation blast.

Considering that the Earth's crust is just 30km thick, I'd think it's pretty safe to say that a planet like our own that was not within the red giant radius but some single digit number of AU away would have its crust bombarded/stripped away and all of the magma underneath with it - leaving (maybe) the iron core as a remnant.

So, if it looks like the sun is going nova tomorrow, forget about building a bunker ;)

Mar 10, 2019
IMHO, Sol's inner planets are lost into or cooked by the Red Giant phase. The 'ice line' moves outwards enough to strip Jupiter's moons and a lot of atmosphere. Think 'Hot Jupiter' season...
Sol's 'single', and too small for a solo supernova, but distant Jovians' iron core might survive such a bang. Due to the star's mass-loss and planet shrinkage, such may be flung 'wide and wild'.....
{ Regret tad terse due to our cat clan helping me type...}

Mar 10, 2019
yep, you guys pretty much defined "clinker" as whatever cindered remains there will be left of the Earth's core.

I was just being concise.

Yeah, I know... What threw you off was me writing a "concise" comment.

If either of you are eager for my poesy? Let me know & I'll see what I can come up with yo fatten it out?

Sorry, at this time I am lacking a feline to encourage a more expansive writing style.

Mar 10, 2019
@Nik, sympathies for the herd of cats dancing on the keyboard because daddy is paying attention to it. I usually have to close the door if I want to type. Then there's the "chasing the cursor" thing.

I think even a red giant would completely vaporize a planet as small as Earth at our distance from the Sun, and it might not even take a million years. Even though it's a rocky planet.

I'd be careful about predicting much iron in the core of Jovian planets; there's another article running right now high on the comment list about unexpected mixing inside Jupiter and Saturn not leaving a well-defined core of heavy elements inside gas giants, and data from Juno and Cassini seem to mutually confirm it not only for different planets but for different measurement methods.

This could be an interesting discussion; I wasn't able to find hard sources easily, so if we want to do a research project and satisfy our curiosity this is a good candidate.

Mar 10, 2019
If, as theorised, much of Jupiter and Saturn innards are 'supercritical' and beyond, unto metallic hydrogen (!!) any nickel / iron metallics are probably dissolved in it, so no 'inner planet' type of solid core need exist...

But, bake with a 'Red Giant' unto 'medium rare', more and more atmosphere may 'puff up' and be blown away like a monstrous comet, leaving less volatile stuff behind. Could this process boil away enough supercritical and metallic hydrogen to precipitate metals etc and create a core ??

Mar 10, 2019
Many stars will fly past us close enough to investigate the planets orbiting them. So every 10 million years or so, man will have a chance to 'switch' to a new Earth. And survive the red giant mode by getting another star to travel with.

Mar 10, 2019
@Nik, the evidence is, they're all mixed up and all evaporate together.

But like I said there's no hard evidence.

Don't be too impressed by metallic hydrogen. It's quite friable once the pressure is mitigated.

Mar 11, 2019
Well now, this brings up an interesting quandary.
We believe we know how the Earth's protecttve Magnetosphere is being pumped out by the Earth's nickel-iron fluid-core as it spins.

So, the question is, what mechanism is producing Jupiter's very powerful magnetosphere?

Considering how different the two cores appear to be to our present knowledge?

Perhaps there are real differences between the magnetic fields produced by the two, very different worlds?

Or is the mixture of metallic hydrogen, with a diffusion of nickel-iron result in a super-generator?

Speculating if maybe some other means or combination of mechanusms we haven't thought of yet?

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