The Future of the Solar System.

[DarkStar7]

Ok so the Sun carrries on burning its fuel eventually becoming a white drawf blah blah blah.

Well, if we ignore my hypothesis of the uncertainty principle producing particles freely out of vacuum of space. Well one thing is not in question the Andromeda galaxy is heading for us, and this will re invigorate the interstellar medium around us...

My question is this... will the dead solar remnant become a seed for a future generation of more massive stars that go Nova which become the seeds of even heavier stars that go Supernova which produce a blackhole?

But what is a Galaxy? isnt it a large version of a stella sized black hole with an acreation disk? So given enough time... what is stopping a stella black hole growing into a supermassive blackhole and a new galaxy?

If the universe is accellerating in expansion.. what if all masses are growing also in unison so the universe is in equalibrium?

[Superewza]

I don't know the answer, just wanted to say that that's a very good question. I hadn't considered that the remnant will probably be interacting directly with the interstellar medium due to loss of a magnetic field...

[JulianO]

My question is this... will the dead solar remnant become a seed for a future generation of more massive stars that go Nova which become the seeds of even heavier stars that go Supernova which produce a blackhole?

Yes - galaxy mergers generally produce a burst of star formation, because of all the gas that was just lying around idle gets mixed up and gets a chance to form new stars.

But what is a Galaxy? isnt it a large version of a stella sized black hole with an acreation disk? So given enough time... what is stopping a stella black hole growing into a supermassive blackhole and a new galaxy?

Well, sort of but its a rather simple view probably. There is a supermassive black hole at the centre of our galaxy, but its not consuming much at the moment, so the accretion disk is not very big. There is probably just not enough stuff in unstable orbit about it to fall in. So it's relatively quiet.

So there is a tiny bit right in the centre where the black hole is important, but the rest of the galaxy goes on about it's business not noticing or caring about the SMBH.

What stops a stellar black hole growing into a supermassive black hole is getting more stuff. So a stellar black hole might start off as 5 or 10 solar masses (5-10 times the mass of our sun). The one at the centre of the galaxy, is 4.1 million solar masses. So one of these stellar black holes would have to consume several million suns to get to the same size. Given the nearest star to us is over 4 light years away, and doesn't show much sign of falling into us, if our sun turned into a black hole (which it won't), it would struggle to find much extra mass at all.

Just because a star becomes a black hole, it doesn't have any greater suckiness - it doesn't suddenly pull stuff in more, it has the same gravitational attraction as the sun it was before - in fact usually less, as the star sheds a lot of material outwards in the supernova explosion. E.g. a 20 solar mass star might end up making a 6 solar mass black hole.

Even if there is enough mass locally to allow it to grow, there is a limit to how fast a black hole can consume stuff - the Eddington limit.

If the universe is accellerating in expansion.. what if all masses are growing also in unison so the universe is in equalibrium?

Well they can't. Black holes grow by swallowing stars and dust. So you take the mass of the black hole, Mb, and throw a sun Ms into it, you end up with Mb+Ms - but thats what you had before. You haven't gained mass over all, you've just moved it around. What was mass in two distinct lumps, is now in all one place. Due to the way gravity works, something relatively distant feels no stronger pull towards this than before.

There is a certain amount of mass in the universe, but outside of exotic theories, it is pretty much fixed (well strictly mass/energy as you can interchange the two).

[DarkStar7]

So if little galaxies with smaller central BHs merge to produce larger galaxies with bigger BHs. At what scale down in the universe does this stop? Is it too simplistic then for me to state it happens all the way down to quantum fluctuations in the void?How else do we produce Supermassive BHs?

Yes, the interstellar medium in our neighbourhood is calm at present, because of the solar wind and our location in the galaxy. But are we all so arrogant to propose that the Suns core will never gather enough mass to collapse in to a BH in the far distance future when there is so much about the cosmos that is not understood.All I know is it's a dog eat dog world and a dog eat dog universe too.

[JulianO]

So if little galaxies with smaller central BHs merge to produce larger galaxies with bigger BHs. At what scale down in the universe does this stop? Is it too simplistic then for me to state it happens all the way down to quantum fluctuations in the void?

I think it is, very small black holes glow white hot and evaporate through Hawking radiation - so don't hang around long enough to get a chance to grow, or at least that's the theory. No one has actually played with a black hole in the lab - and probably a good thing too!

How else do we produce Supermassive BHs?

No one quite knows, there are theories, but none of them really solid. You need a way to funnel vast amounts of matter into them in some way. You can't wait for stuff just to drift in, they would never grow as big as we see them in the time available. So astronomers postulates streams of matter slowed by friction so it can drop into them from much further out in the galaxy.

Yes, the interstellar medium in our neighbourhood is calm at present, because of the solar wind and our location in the galaxy. But are we all so arrogant to propose that the Suns core will never gather enough mass to collapse in to a BH in the far distance future when there is so much about the cosmos that is not understood.All I know is it's a dog eat dog world and a dog eat dog universe too.

Of course anything is possible, but it has to gather a LOT of matter to make it to a black hole. You need about 10 solar masses to make a star with a chance of going supernova.

Maybe more to make one that can leave a black hole. So, the star has to find and consume the equivalent of another 9 or more suns. If you add up all the mass in the solar system without the sun, you get less than 1% of the mass of the sun, so consuming all the planets and dust and stuff won't make any significant difference, you need a lot of matter from outside the solar system.

And lets not forget the sun loses about 2 billion kilograms of mass a second through burning fuel!

As far as we know, in the 5 billion years the sun has been around, it hasn't consumed any other suns. It has 5 billion years left, so you'd have to say on balance it won't be consuming any other stellar like objects in that time without some radical shake up in the cosmic environment.

[Space Bat]

The sun does have an unfortunate habit of being hit by comets quite frequently...however this would in no way assist with delaying the lifespan

[phat tony]

if the sun was getting hit by matter would it not be refueling, and could you not refuel the sun or feed it if you want, i do know it would need a crazy amount of food but would it not be doable.

[digitaltre515]

Our sun, as Julian said, just can't go supernova without lots of outside mass. This is why the majority of supernovae (type 1A) are binary systems in which a smaller, dense companion star consumes the mass from its bigger brother. Once it reaches 1.4 solar masses it always goes supernova. For a single-star supernova (type II) you need a star that is something on the order of several thousand solar masses; a supergiant. Those stars go supernova at the end of their relatively short lives once their fuel has begun to degrade from H into He and so on until they make iron. After they start making iron they have literally seconds until they go supernova. It's these stars that become black holes, pulsars, neutron stars, etc. Rarely, you get the truly exotic: a quasar, which seem to be very old remnants of ancient galaxy formations at the birth of young galaxies. And this makes sense, because a quasar is a black hole which is consuming matter so rapidly that it begins to reject matter consumed by converting it into a high-powered death ray of X-rays and gamma rays. These seem to be linked to the birth of galaxies (as they are found only in the most distant galaxies we've found) and probably the formation of super massive blackholes.

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I am here: http://maps.google.com/maps?ll=32.288164,-81.207359

[Lancashire Astroguy]

if the sun was getting hit by matter would it not be refueling, and could you not refuel the sun or feed it if you want, i do know it would need a crazy amount of food but would it not be doable.

In theory, the Sun could be "refuelled" to give it a longer lifespan, but you would have to add at least a few hundred Jupiter-masses of hydrogen to make a significant difference and this would have to occur whilst the Sun was still in the main sequence stage of its life.

In fact there is a type of star that exists in globular clusters called a "blue straggler" which despite their brethren having evolved into red giant stars, they still lie on the main sequence, as if they were a much younger star. One theory is that these stars have been formed by the merger of 2 previous stars, with the extra hydrogen brought into the mix prolonging their lifespan. Such mergers can occur in globular clusters because of the proximity of the stars.

The question is though if you are capable of moving hundreds of Jupiter masses worth of Hydrogen across the galaxy, would it not be simpler just to move the human race to another solar system?

Regards, James

[phat tony]

it would be a lot easier to move people rather than planets but i don't think it would be safer. not yet any way. wow moving planets would be some job, some would say only in fiction but who are we to know what the future will hold LOL. i dont see us ever wanting to feed the sun, but as you mentioned it could eat a healthy diet that could keep it serving us LOL.

[Space Bat]

Suggest watching the film Sunshine

[DarkStar7]

I agree with the current view along with Juliano that the Sun at present is not increasing in mass. It has not over the last 5billion yrs and will not in the next 5billion years. However when the Sun dies and the solar wind umbrella has collapsed, the cooling Stella remnant will be around well.. till the end of time. That is along time to absorb dark matter from the void and any gas reignited by passing galaxies. Ok let's turn the question on its head.. Will the Stella corpse ever get smaller? I cant see how?

[JulianO]

If a white dwarf gets bigger than the Chandrasekhar limit then it will go off pop, and expel material. On the other hand, it seems even white dwarves have stellar wind, so its a case of is their feeble stellar wind greater or lesser than the accretion of dust and other junk, something looked into in a by others.

Prevention of accretion onto white dwarfs by stellar winds

[PeterJB]

I've often wondered what the fate of the Gas Giants and Kuiper Belt objects will be when the Sun dies. Mercury, Venus and Earth will almost certainly be consumed by the red giant sun, Mars would probably destroyed when the Sun finally sheds it's outer layers. But would the gas giants survive and continue to orbit the white dwarf? I'd have though at least Neptune would be far enough away to survive it.

[JulianO]

I'd guess something will survive, though I suspect the atmosphere's will be stripped back somewhat. We're finding lots of hot Jupiters around other planets, some orbiting VERY close to their parent.

[DarkStar7]

I wonder if Venus was originally a hot Jupiter before the majority of its atmosphere was burned off into a long tail like a comet. I believe the process is still going on.

[Macavity]

Article in this months (March) S@N:

"Scorched worlds found near red giant".

Citing link to: NASA - Kepler