solar regulation question

[hoola]

If the sun, as predicted, will uncomfortably expand in the far future, couldn't a process be developed of sending mechanisms to enter the solar core to fission the heavier elements before that becomes a critical issue, thus maintaining an appropriate ratio and so keeping the unwanted eventuality at bay?

Edited August 2, 2018 by hoola

[Sensei]

1 hour ago, hoola said:

If the sun, as predicted, will uncomfortably expand in the far future, couldn't a process be developed of sending mechanisms to enter the solar core to fission the heavier elements before that becomes a critical issue, thus maintaining an appropriate ratio and so keeping the unwanted eventuality at bay?

Introduction of Iron, or some few other heavier elements, indeed can decrease temperature inside of the core of the Sun.

But I am afraid so, there is not enough of Iron in the entire Solar system to do it on mass scale.

Fe+Fe requires energy to fuse together (and product Te-108 is not stable). That energy is taken from core decreasing its temperature, and regular fusion processes are stopped. If it is happening rapidly, outer layers of star, collapses toward core. They accelerate to significant or even relativistic velocities.. What will happens next depends on their velocity/kinetic energy. During collision of outer layer particles with remains of core particles there can be created pair of electron-positron, or neutrons, photodisintegration, and other high energy physics reactions. That's what happens in various types of nova/supernova explosions.

1 hour ago, hoola said:

couldn't a process be developed of sending mechanisms to enter the solar core to fission the heavier elements before that becomes a critical issue

Fission is releasing energy..

It's not what will happen inside of so small star as the Sun.

Problems with the Sun will start when 3x He-4 fuse together to make C-12. And then C-12 will fuse with He-4 to make O-16. And so on. It's not in even close to fissile elements..

 

 

Edited August 2, 2018 by Sensei

[hoola]

so you are saying that the C-12 fusing with He-4, and other steps in the stellar process make the idea unworkable? Is that judged by current technological means, or by some theoretical insurmountable barrier  that a technology in a billion years or so could not figure a way around?  You said that fission doesn't take  place inside our sun, but  I am saying that the fissioning be performed by selected removal of the heavy elements, brought to some suitable place, perhaps outside the sun itself for reduction, and the lighter elements then replaced to the center.The fissioning mechanisms could borrow energy from the normal fusion of the sun to perform that work, thereby making the process more energy neutral...

[Sensei]

What is doable is placing mirrors/filters in cosmic space between the Sun and our planet, and this way disallowing too large radiation to arrive to planet surface. Filters which will just reflect, or reflect and harvest energy to use it by human population. Polarization filter reflects 50% and pass through remaining 50%. Two polarization filters, one by another, with adjustable angles can allow remote control how much of energy arrives between 50%..0%.

42 minutes ago, hoola said:

Is that judged by current technological means, or by some theoretical insurmountable barrier  that a technology in a billion years or so could not figure a way around? 

There are two types of reactions endoenergetic and exoenergetic (endothermic and exothermic).

One requires input of energy from external source, other one is releasing energy to environment.

Either nuclear fusion is releasing energy, and nuclear fission is releasing energy.

Photodisintegration, or creation of free neutrons, are examples of reactions in which missing energy required to split nucleus is arriving from external source.

To "remove" Carbon-12 or Oxygen-16 atoms from the core of the Sun, you would need even more energy to split them. It's called induced radioactivity.

(rest-mass of C-12 nucleus + rest-mass of He-4 is higher than rest-mass of O-16)

How to prevent burning of Helium-4, Carbon-12 or Oxygen-16 etc. in the core of star? Decrease core temperature. At lower temperature there will be less reactions per second happening. Extremely tricky business. One mistake in calculations and there can be too much decrease of temperature and everybody would die in global ice age.

Edited August 2, 2018 by Sensei

[hoola]

placing mirrors in space is not what I am referring to, that is a temporary patch, and won't prevent the eventual swelling of the sun and the destruction of earth...can't some theoretical process be available to "recycle" the stellar interior? If the heavier components can be removed to a remote location, say to an orbiting fission based "artificial star" that directs surplus energy to a narrow beam of high energy photons exiting the solar system, while the hydrogen is ferried back to the sun?

[Sensei]

1 hour ago, hoola said:

placing mirrors in space is not what I am referring to, that is a temporary patch,

Temporary for billions of years..

 

If the all "temporary patches" would be so good...

 

Edited August 2, 2018 by Sensei

[hoola]

 I ask the question in a theoretical sense, which gives some intuition as to what large scale project an advanced civilization might be doing with their time as they persist for billions of years.....a temporary mirror solution of the buck rogers level is  not what one would hope  of the truly advanced.  Could an artificial  fission based companion star  be theoretically possible to construct? It does seem that if it can, the excess  energy could be "dumped" outside of the solar system....perhaps by a particle or laser beam directed into a distant black hole  or empty space. Also, if it is possible to build one, would that give some way for us to detect another civilization who had built one for the stated purpose? I presume that the analysis of a distant artificial fusion star would be distinctive

Edited August 2, 2018 by hoola

[Janus]

4 hours ago, hoola said:

If the sun, as predicted, will uncomfortably expand in the far future, couldn't a process be developed of sending mechanisms to enter the solar core to fission the heavier elements before that becomes a critical issue, thus maintaining an appropriate ratio and so keeping the unwanted eventuality at bay?

The Sun is presently fusing hydrogen to helium at the core.  When the percentage of helium in the core builds up enough the Sun will go into "shell burning" mode where it fuses hydrogne in a shell surrounding the helium core. This is when it will leave the main sequence and begin to swell into a red giant. Even before then, the build up of helium in the core will increase the density and increase the rate of over all fusion. Even while it is in the main sequence it is slowly warming up.  

To cause the Helium to undergo fission would require a net input of energy, as is the case for any isotope lighter than Iron 56.  The net input would have to be at least as much as the energy released by the original formation of the helium through the fusion of hydrogen.  So you would need to have an energy source sufficient to do this, be able to get it to the core of the Sun, and apply it in such a way as to just cause helium to fission into hydrogen.  If you've got that type of technology at hand,  you could just move the Earth out of the solar system and use this energy source to substitute for the missing Sun (keep in mind, in order to just maintain the present hydrogen/helium ratio at a constant in the Sun you would have to supply energy at the same rate as the whole Sun outputs it and the Earth only intercepts less than 1/2,000,000,000 of that energy, so if you've got an energy source )

So let's say that you've got such an energy source, it could produce enough energy in just 83 days to move the Earth out of the Solar system.  Since you could slowly move the Earth away from the Sun as it warms up,  you wouldn't even need to produce energy at this rate.  And it would be much easier to implement than trying to prevent the Sun from heating up.

[Sensei]

6 hours ago, hoola said:

I ask the question in a theoretical sense, which gives some intuition as to what large scale project an advanced civilization might be doing with their time as they persist for billions of years.....

What they are making with their free time? They're making simulations of the Universe.. to test how Universe with different input parameters will evolve.. starting from mass of electron, mass of proton, speed of light, different random number generator routine, and so on..

 

 

Programmer's dream holiday "code your own Universe simulation in 7 days"..

 

[hoola]

that might be of interest to someone of our time,  but that form of numerical analysis would have long been sorted out and become of academic interest only to historians..What is predictable is the destabilization of their solar system, and a presumed logical desire to halt that process. Your thinking seems guided by the current rage of video game addiction, which is what you are describing that they are  doing with simulations of fake universes.