Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
"Bun is such a sad word, is it not?" -- Watt, "Waiting for Godot"

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.



Saving the Sun

In the long run this will also save the Earth!
  (+20, -10)(+20, -10)
(+20, -10)
  [vote for,

(Suggestion: need a "Save the World" category; I couldn't find a category that really fits this Idea.)

Astrophysicists say that over its lifetime the Sun's brightness has increased by 30% from its original intensity. And it will get even brighter in the future. Thus, while the Sun will use up most of its hydrogen fuel after four or five more billion years, and then expand into a Red Giant type of star, and cook the Earth, EVEN BEFORE THEN, less than a billion years from now, the slowly increasing radiance from the Sun will make the Earth uninhabitable, "prematurely", so to speak.

What to do? One suggestion I've made elsewhere is to put big mirrors in space to block out the excess sunlight. But this is obviously a fragile and untrustworty solution. There has to be a better way!

So, let's directly operate on the Sun itself. Its brightness is fairly directly related to its total mass. If we could remove a significant chunk of its mass, then its brightness would be naturally reduced, and, while it probably would slowly again increase in brightness, the process would take a rather longer time than before, to make the Earth uninhabitable. Why, we might even be able to postpone its expansion to Red Giant stage by several billion years!

OK, now how much mass are we talking about here? VASTLY ENORMOUS QUANTITIES! That's what makes this a Half-Baked Idea, of course. But don't let that stop us from thinking about it, because it is a possible thing to do!

To be a bit more precise, while still invoking some rather rounded numbers, the Sun is about 1,000 times the mass of Jupiter, and about 1 million times the mass of the Earth. Astrophysicists say that for a star to exist at all as a gravity-confined hydrogen-fusion reactor, its minimum mass must be about 80 times that of Jupiter. Such a star will fuse hydrogen so slowly that it might take literally a trillion years to use up its fuel. Keep that in mind for later.

Next, all mass that a star possesses, above the minimum amount, merely causes it to burn brighter and live a shorter life. The very biggest and most massive stars (about 200 times that of the Sun) live no longer than a few tens of millions of years, before blowing up as supernovae. Our Sun is a middle-of-the-range average star, and is halfway through its normal life expectancy.

Next, the Sun is currently already LOSING mass at a rather large rate. For example, the Solar Wind is spewing mass in all directions at a rate of a million tons per second. MORE, that radiated sunlight mentioned at the start of this post is Energy which is Equivalent to Mass, about 4 million tons per second. But it is also a mere trickle, compared to the total mass of the Sun. That's why it can keep doing this for another 4 or 5 billion years, and STILL be able to expand to a huge Red Giant!

I estimate that we need to remove somewhere between 1% and 5% of the Sun's mass, to solve the increasing-brightness problem. That would be, of course, a quantity of matter equal to 10-to-50 Jupiters. Removing this mass will have two significant effects, only one of which is brightness related. The other is gravity related; the Sun's gravity keeps the planets in their orbits, after all. Reducing the mass of the Sun means that the orbits of the planets will grow a bit larger. But they will all do this in sync, so I see no major problem ("Worlds in Collision") that some people might worry about. As far as the Earth is concerned, BOTH a slightly larger orbit and a reduced Solar radiance will stave off the premature end of the world. --And no, we don't have to worry about a permanent Ice Age, since once we start removing massive quantities of matter from the Sun, we can stop at any point we like, keeping the Earth safe. Also, of course, we can USE the Greenhouse Effect to keep the world warm....

OK, now how do we do this thing, removing vastly enormous amounts of material from the Sun? Jets! Astrophysicists have discovered that during the formation of a stellar system, the star being born is also spewing two major jets of matter outwards from its magnetic poles. I propose that we build an appropriate magnetic apparatus to start the Sun's jets up again!

That apparatus will likely consist of many millions of miles of superconducting cable, wrapped around the Sun. It IS just a big ball of magnetically controllable plasma, after all! In fact, these wrappings probably do not need to be in orbit around the Sun, because their blockage and redirection of the Solar wind (for starters!) may be sufficient to hold them up. To be determined.

TURNING UP THE POWER of these magnetic wrappings will put a kind of Squeeze on the Sun. Mirrors can reflect equatorial light to the polar regions, to heat them up even more than usual. Between the Squeeze and the extra heat and the guidance of the Solar Wind toward the poles, I expect the jets to begin. Their spewings will eventually reach interstellar space, say half a light-year from the sun (birthing jets extend for multiple light-years). That's where we will have prepared MORE magnetic wrappings to CATCH those jets, and cool them and coalesce them into many bodies of frozen hydrogen. We can also magnetically filter out (see "mass spectroscopy") all sorts of good stuff like iron and gold and titanium and so on, and mostly just pile hydrogen into our artificial worlds (we don't want them too big, because that just means we waste energy getting at the hydrogen later). Think of them as "fuel tanks" for our civilization's fusion reactors, for billions of years to come.

All the preceding is just Part One of what I have in mind. Remember that trillion years...?
Part Two

The ElectroMagnetic Force is ten million billion trillion trillion (10E40) times stronger than the force of Gravitation. An ordinary feeble refrigerator magnet is more powerful than the entire mass of Planet Earth, when it comes to attracting a steel needle upward vs. downward. However, Gravitation is cumulative, while ElectroMagnetism always exhibits opposites that cancel each other out over long distances. Thus does Gravity rule the Universe. Nevertheless, "short" distances for ElectroMagnetism (especially easy for the Magnetism aspect) can still be millions of kilometers, and so stars and planets are often accompanied by enormous magnetic fields (even though also often weaker than a refrigerator magnet, throughout most of the volume of Space occupied by those fields).

This part of this Plan for Saving the Sun will require three extremely powerful sets of magnetic apparatus, and not just one. Possibly the two that were originally located in the Oort Cloud (see Part One above) can be enhanced and reused for the current purpose. The three units are to be lined up something like this (where N and S represent magnetic poles):
{(S)(to fill)(N)}...{(N)(Sun)(S)}...{(S)(to fill)(N)}
Each apparatus is designated by the stuff inside the brace {} symbols. They are to be oriented such that the two which are located on either side of the Sun are positioned "above" and "below" the overall "orbital ecliptic plane" of the Solar System. The distance between each apparatus should be no more than 10 million kilometers, so a fair amount of thermal shielding is certainly going to be necessary. I assume all problems of that sort were solved back in Part One. It is imperative that the strength of these magnetic fields be sufficient to keep the Sun's gravity from pulling in the two distant units; they must "magnetically levitate" at the chosen distance.

Assuming that Part One does the job of protecting the Earth until the Sun enters the Red Giant stage, then the point where Part Two is put into operation is just a few millenia before helium fusion is about to begin, in the Solar core. As I indicated in one of the annotations, helium fusion releases extra energy which is the cause of an old star's expansion into a Red Giant. We are going to prevent this!

With the three sets of magnetic apparatus in place, we use the middle one just as in Part One, to activate jets that remove mass from the Sun. Each jet is collected and FILTERED and coalesced by one of the levitating apparatus. The filtering process is usually known as "mass spectroscopy", and is done purely with magnetic fields acting upon electrically charged particles (the jets purely consist of that...). We coalesce 90% hydrogen and 10% helium, and spew the rest (the filtered-out stuff) off toward the Oort Cloud, where it can be collected and saved (all the chemical elements heavier than helium, trillions and trillions of tons of everything up to lead). Please note that the filtered-out stuff will constitute only about 2% of the total mass of the Sun, about 20 Jupiter-masses, and most of it will be helium. (Imagine what we could BUILD with 10 Jupiter-masses worth of iron, copper, titanium, aluminum, etc.; this is stuff the Sun has been carrying around ever since it was born) Now remember all those frozen worlds of hydrogen we saved in the Oort Cloud back in Part One? We want to REPLACE the mass we are now removing from the Sun, with some of that saved material; we send it back from the Oort Cloud to the two coalescence points.

OK, as the jets do their thing, and the filtering and coalescing of the jets (and of the arriving Oort material) goes on, there is a kind-of-funny thing that happens to the Sun's gravity upon the Solar System: Almost Nothing! See, the total mass of the Sun is STILL approximately in its original place, at the center of the Solar System! The total gravitation of these three nearby perpendicular-to-the-ecliptic collections of mass will have just about the same effect upon the planets as if that mass was still concentrated in one place. Even Mercury is something like 58 million kilometers from the three sets of magnetic apparatus (one being 10Mkm above the orbital plane, and one being 10Mkm below).

Next, as the jets continue, the Sun will get less and less bright. But as the coalescence continues, eventually the two levitating bodies will pass the 80-Jupiter mark, and they will become new (very dim) stars! Yes, we are going to have to use care to ensure the Earth receives enough light while all this is going on -- by using huge mirrors in Space as before, no doubt. Oh, and you can see that I wasn't kidding, about needing extremely strong magnetic fields for the levitating units. There is a peculiarity about the Gravitational Force Equation which explains this....

F=Gm1m2/dd (Force = [Gravitational Constant][mass 1][mass2] / [distance][distance]). Suppose the mass of the Sun is 1 trillion times the mass of the initially empty levitating magnetic apparatus. Then the gravitational attraction is related to the Mass1 and Mass2 values of [1 trillion] multiplied by [1]. If 10% of the mass of the Sun is transported to just one levitating apparatus, then the gravitational attraction becomes related to [900 billion] multiplied by [100 billion and 1]. This is MUCH MORE attractive Force than when the process of coalescing the jets began! So, as the coalescence process goes on, we have to increase the strengths of our magnetically repulsive apparatus. The maximum forces will be reached when 2/3 of the mass of the Sun has been jetted off to the two coalescent points, but remember that the engineering to accommodate this will have had billions of years (from NOW) to become prepared for it!

Next, as the jets continue, the Sun continues to shrink. The gravitational pressures that cause fusions to occur will become less and less, and eventually stop. The "degenerate matter" innermost core of the Sun will reintegrate into ordinary matter and expand to occupy the space of the mass that is being jetted away. The filtering process continues, and ALL the helium "ash" that had accumulated across (about) 10 billion years of shining is eventually removed, as finally the Sun is entirely split into two newly-coalesced stars. Two YOUNG stars, with NO "ash" in their cores!

Finally, we REVERSE the entire process, but SLOOOWWWWLLY. The problem here is that we only want ONE jet from each of our new stars, re-coalescing back at the original site of the Sun. Remember Action and Reaction? Slow jets will allow us to let the two stars' Gravity keep them from accelerating out of the Solar System altogether. (With opposite jets from the original Sun, this was not a problem. Also, the POSITIONS of coalescence was maintained (the jets had to be STOPPED) by the spewings of the filtered matter off toward the Oort Cloud -- very fast jets, those spewings were!)

Anyway, we don't have to do any more filtering, as we carefully put the Sun back together. When done, we are guaranteed another full 9 or 10 billion years of Sunlight for Earth, before we have to do it again! I don't know how many times we can do this, before we have to start scouring the Galaxy for hydrogen to replace all the helium that the Sun will eventually create, but it seems to me that, especially by taking lots of OTHER stars apart (lifeless star-systems only, of course!), just to save their fuel for our Sun, we could probably manage for a trillion years, or even more.

Vernon, Dec 17 2004

Destroy the Sun http://www.fastlane.../index.cgi?sol.html
If you're not part of the solution... [Detly, Dec 17 2004]

Fission and fussion in a super nova http://curious.astr...tion.php?number=599
Fission fusion processes [madness, Dec 23 2004]

General Relativity and Energy Conservation http://groups-beta....&d#4ac14088f9cf2d42
Part of a discussion, related to one of the annos here. [Vernon, Dec 23 2004]

"The Last Question" http://dookaloosy.d..._book_-_Asimov1.htm
I don't know how long this link will last, because for almost anyone to post a story like that probably violates the copyright. [Vernon, Dec 23 2004]

Total Conversion Total_20Conversion
Yup, with enough trillions of years, we might be able to do something along those lines... :) [Vernon, Dec 24 2004, last modified Dec 31 2004]

On Thinking Bigger http://www.physicsf...4400691#post4400691
If I had been able to make some sort of "invention" out of that post, I would have posted it somewhere here at the HalfBakery. [Vernon, May 31 2013]


zigness, Dec 17 2004

       [Vernon], you think BIG!
Ling, Dec 17 2004

       [Vernon]! You're thinking about this in entirely the wrong way! See link.
Detly, Dec 17 2004

       Thanks [Tabs], you saved me some time there.By the the time I would've got to the bottom it would be night time.
skinflaps, Dec 17 2004

       [Detly], it seems to me that toning down the Sun's radiance will solve many of the problems mentioned at that linked site.
Vernon, Dec 17 2004

       That is true, and so we will observe your project with great interest. Perhaps, within the solution to your problem, lies the solution to ours.   

       The site is mine, by the way.
Detly, Dec 17 2004

       //That apparatus will likely consist of many millions of miles of superconducting cable, wrapped around the Sun.//   

       Assuming this idea is not meant as pure fiction (is it?), where will you get the cables from? Your talking about a mass of cables that has more volume than possibly all the planets in the solar system. Does this fall under the "magic" mfd category in the help file?
energy guy, Dec 17 2004

       [Vernon], what is the mechanism that makes the Sun finally expand? Is it the reduced mass or fuel, and hence the changing balance of expansion "pressure" vs. gravity?
If it is reduced mass, or even diminished quantities of hydrogen fuel, then find more fuel! Throw some more coal on the fire.
Ling, Dec 17 2004

       //That apparatus will likely consist of many millions of miles of superconducting cable, wrapped around the Sun.//   

       Wouldn't that throw enough shade right there?   

       As the sun used up it's fuel, and got too dim, then we could put the removed matter back in!   


DesertFox, Dec 17 2004

       I see you folks have found a couple of the sticking points. Regarding the mass of cable, you should assume that we have full access to the Oort Cloud for material by the time this project has to be done. Also, metallic hydrogen may be available as a superconductor, but I admit that's speculative. Still this IS the HalfBakery....   

       Regarding the cable blocking the sunlight, I thought of that, too. We will certainly be able to place mirrors all through the region between Sun and Earth, to ensure enough light reaches the Earth, even if we need to reflect light from the JETS at the Earth.   

       The future expansion of a star to Red Giant is caused when the core of the star starts to fuse helium 'ash' as well as hydrogen (from whence the 'ash' comes). Extra fusions = extra heat = extra force to fight gravity = expanding star.
Vernon, Dec 17 2004

       Would it not be substantially cheaper to simply shield the Earth?
theircompetitor, Dec 17 2004

       [theircompetitor], yes, it would be cheaper, over the short run. But include 5 billion years of maintenence, however (and assume civilization is always present to maintain the shields), perhaps not such a smart investment.
Vernon, Dec 17 2004

       Whew! Just read all of [Vernon]'s idea (+) and [detly]'s (+). You are both on different sides of a totally unhinged argument. If this gets baked I will move into the lucrative superconductor manufacturing sector - there'll be a fat contract there.   

       [detly] - nice site!
wagster, Dec 17 2004

       [V] - you are a glass half empty kind of guy. The problem is that the sun will run out of hydrogen and in the process of converting over to run on helium will get brighter. There was an article about this in this months Natural History. It seems to me that cutting out a piece of sun will dim it, as you say, but only make it run out of hydrogen faster - the outside bits which we would remove are likely to be the most hydrogen rich.   

       Your proposal could be adapted to feed the sun more hydrogen and maintain the status quo. A small, young, hydrogen rich star could be wrapped in your coils, and its own solar wind used to propel it into our sun. This would replenish the hydrogen fuel. It might take a while to move a star, but there are several million years to work with.   

       It occurs to me that bringing in two small young suns instead of one might help neutralize any gravitational problems a new sun in the system might cause. The could be brought in from opposite directions to cancel each other out.
bungston, Dec 17 2004

       Oh yeah. That'll be much better.... ;-)
wagster, Dec 17 2004

       Cliff notes version: Build ring around sun to magnetically draw out mass (like nuclear control rods) to throttle reaction rates to control the output & lengthen life.   

       Vernon, you were doing so well with shorter ideas lately, what happened?   

       Still, a neat idea. Although, it seems easier to just move the earth further away or closer as needed, or to colonize other planets, or countless cheaper ways to solve the same problem.
sophocles, Dec 18 2004

       I don't think those short ideas were really Vernon. I think he was renting out his account for other bakers who wanted that Vernon mystique.
bungston, Dec 18 2004

       Thanks [wags] :) It doesn't get much done on it when I don't have real work to avoid.
Detly, Dec 20 2004

       [bungston], I'm pretty sure you are neglecting one key piece of the mass/brightness issue. The more massive a star, the EVEN-faster it burns its fuel. It is not a one-for-one thing. The reverse of that is, reducing the mass of the Sun by 1% will cause MORE than a 1% reduction in its fusion rate. It is that rate which controls the lifetime of the star, moreso than its fuel supply.   

       Also, I've read that the "degenerate matter" innermost core of the Sun does not much exchange material with the outer parts of its core. Which means the Sun's lifetime supply of hydrogen fuel is pretty much already part of the innermost core...so that is another reason why removing a couple of percent from the outer regions shouldn't cause any problem.   

       Finally, all those short ideas with my name attached are indeed mine. They just didn't need the kind of background information that this one did.
Vernon, Dec 20 2004

       The Sun is the center point which all planets revolve around in this solar system. Changing it's mass unnaturally will make planetary orbits unstable and cause major ecological disasters. Imagine how Earth would be like if Saturn slammed into us. Definitely (-).
croissantz, Dec 20 2004

       [croissantz] we're saving the sun first. We can save the planets later.
sophocles, Dec 20 2004

       [croissantz], you are mistaken. The planetary orbits will not automatically become unstable just because the Sun loses say, 2% of its mass. Because this is a long-term project, and moving that much mass around will take time. So, AS the Sun slowly loses mass, the planetary orbits will just as slowly expand slightly. All of them at the same time. Remember, each planet is moving in its current orbit at a certain velocity. If we could "bump" that velocity a bit (the way we do with artificial satellites around Earth), then the planet would be impelled to take a slightly larger orbit. Similarly/equivalently, if the source of gravitation, the Sun (which causes a planetary velocity to curve into an orbit) is reduced, then the planet's velocity is now faster for its distance-from-the-Sun, JUST as if its velocity had been bumped instead.
Vernon, Dec 20 2004

       If we were to change orbits outward, wouldn't it get a lot colder?   

       Actually, you might be on to something. If the sun is burning a bit brighter as it loses mass, then perhaps what we need is a slightly increasing orbit.
RayfordSteele, Dec 21 2004

       [RayfordSteele], that is precisely why I estimated that only 1% to 5% of the Sun's mass be removed. Too much of a good thing is not a good thing, and all that.   

       One "funny" aspect to this is thinking about the fact that the Sun is 30% brighter now than originally. Yet removing 1% of the Sun's mass might be expected to reduce the brightness by say 2%, and also to allow the Earth's orbit to expand by another 1% or so, --which by Inverse-Square Law means brightness impinging upon the Eath also goes down even more, maybe another 2%. So, let's assume a total 4% reduction in light received by the Earth. In terms of today's atmospheric composition, this is very significant, and could immediately be expected to lead to a global Ice Age. YET IN PREVIOUS EONS the received sunlight had been that much less than now, and the Earth was warm!!!   

       The answer is that the Earth's life-system (Gaea?) has responded to the increasing Solar brightness by removing carbon dioxide from the atmosphere for millions of years. All that CO2 previously helped the world stay warm under lesser sunlight. It is partly because so little was left to take out that in less than a billion years (I think I've seen estimates of only 300 million years), further slow increase in the Sun's brightness will doom the Earth.   

       And nowadays, of course, we are putting vast amounts of CO2 BACK into the air by burning fossil fuels. Not smart! The long-term survival of the Earth depends on accessing Space, putting temporary Sun-Shields in place, and then invoking a more permanent fix for the Solar-brightness problem. Such as this Idea here.
Vernon, Dec 21 2004


       Or possibly even physics.
Detly, Dec 21 2004

       //Remember that trillion years...?//   

       No sorry I was at the toilet.
etherman, Dec 21 2004

       If we're advanced enough to build a superconducting sphere round the sun, put sufficient power into them to disrupt its behaviour and create huge hydrogen plumes half a light year in length and then travel half a light year to collect them at the other end, why do we need to worry about keeping Earth habitable? We'd need to get millions of people off-planet to carry this project out... evacuating the place and setting out for pastures new would be easier than this, if anything. If we ever have that kind of skilled workforce, dedication and funding, maybe it could be better used, say on something trifling like third world sanitation.   

       In short, if we could do this, it wouldn't be on the priority list.
david_scothern, Dec 21 2004

       [david_scothern], you are assuming that such a civilization will not EVER self-destruct. I say humanity needs to ensure itself a safe haven to recover. One in which we won't all be broiled before the recovery is finished. Several times (self-destruction and recovery) if necessary, just to take as few chances as possible with our ultimate survival. Sure, we may have 300 million years left, and the human species might die off for other reasons altogether before then, or even evolve into something else, but 4 billion years of Life On Earth is doomed unless Intelligence acts to save it. If God is absent, then consider it a debt we owe to the biosphere in which we were born as a species. If God is present, well, there still may be a debt of some sort to the Earth (we have "dominion" and as such have responsibilities as caretakers), and besides, some generosity won't hurt. Machines that make machines will be doing most of the work!
Vernon, Dec 21 2004

       [Vernon], If I assume that your system is implemented, and indeed the Earth is saved from doom in 300 million years or so (and if any of you guys are reading this archive in 300 million years - well done!), how long would you expect the stability to last?
What would happen after that?
Isn't the solution 'temporary' (if I can call it that)?
So shouldn't you call your idea "Temporarily saving the Sun"? :P
Ling, Dec 21 2004

       [Ling], well, partly yes and partly no. The overall doom of the Earth by the Red Giant Sun in about 5 billion years can only be postponed by removing so much mass that the Earth would freeze instead of broil. So, this is kind-of why I mentioned that removing up to 5% of the mass of the Sun might be the thing to do. Probably not actually that much need be done, however, to get total 25% or so reduction (because of the orbit-enlarging side-effect). The idea is that by reducing Sunlight ENOUGH, and adding enough CO2 to provide sufficient balancing greenhouse effect, then the Earth can REPEAT the sequence of the last several billion years, in which the Sun grew gradually brighter while the biosphere removed CO2. Then only the Red Giant problem remains. That's where the second part of this Idea comes in....
Vernon, Dec 21 2004

       I believe any sun modification could be done more efficiently with antimatter. Just build a bunch of matter/antimatter emitters, and shoot the sun with them as needed.   

       Of course, technology will be several orders of magnitude more refined in by the time something must be done, so I'm not very worried.
Madai, Dec 21 2004

       The problem with shooting antimatter at the sun is that it would get rid of the hydrogen by converting it to energy, If you could make antimatter, you could probably make something to join the hydrogen into non-fusible heavy elements like iron. These could just be dropped into the sun to dispose of them.   

       I seem to remember in Clarke's 2010 that they did something like this with Jupiter. It was never exactly clear to me what the monoliths were up to, but they swarmed over Jupiter and by doing so converted it into a star. I presume they were collecting gas and turrning into heavy elements, thus increasing Jupiter's density to the point where fusion happened.
bungston, Dec 21 2004

       i had no idea my page had the ability to scroll so far.
benfrost, Dec 23 2004

       [It IS just a big ball of magnetically controllable plasma, after all!]   

       This idea really just deals with the symptoms it is not a cure. If the earth/man is going to last out till the end then we need a more long term solution. What happens when all the hydrogen is gone?   

       Can you explore the possibilities of an electro-magnetically protected "processing plant" at the center (or somewhere appropriate) within the sun? The purpose of the core is to process the byproducts of the suns fusion reaction...   

       Naturally I was thinking that the core would be a fission reactor... not necessarily for providing energy but for producing hydrogen. Since sun is not made entirely of Hydrogen and Helium we can choose an appropriate fission reaction whose by products include hydrogen...
madness, Dec 23 2004

       Well I figure that is what Veron was on about if it was a bit long winded... Vernon's idea is to pump out all the helium in the sun and replace it with hydrogen from somewhere.   

       Why can't we use all the knowledge gained making fission reactors to process the by products of the sun... (oops try not to quote the 2LOTD at me).   

       By the way I thought current theories regarding the stability of stars included dynamically balanced fusion and fission reactions.....
madness, Dec 23 2004

       [madness], you are trying to get something for nothing. Due to the fact that fusion of hydrogen to helium releases energy, if you want to fission helium up back into hydrogen, then you have to put that same amount of energy BACK. With respect to fusions and fissions involving other elements, well, fusions of light elements such that the result approaches Iron all release energy, and fission of heavy elements, such that the pieces are at least as heavy as Iron, also release energy. All the chemical elements heavier than Iron were made during supernova explosions, where energy was available to pay for fusing heavy atoms together. THAT is the energy we get back by fission.   

       Next, fusion of hydrogen is much more efficient at producing energy than is the fission of uranium or plutonium (a greater percentage of total mass is converted to energy). Also, all those fissionable elements are quite rare in the Universe, compared to hydrogen. So, if we put some effort into preventing hydrogen from being wastefully fused in lifeless star systems (to say nothing of all the loose gas clouds in Space where stars are still being born), there really would be sufficient quantites of the stuff for our Sun (regularly rejuvinated), for many many trillions of years.
Vernon, Dec 23 2004

       Perhaps the reverse would be easier: adding mass to make the sun cooler. Of course, you need the right element—an element that would poison the fusion reactions.
ldischler, Dec 23 2004

       [hey vernon] Yip I tend to run very close to the wind when it comes to "getting something for nothing"... but anyway, as I understand it both fusion and fission reactions release engery because the mass of the resultants is less than the mass of the reactants --- no laws are violated since mass is lost from the system as energy.   

       I agree with you that as far as we know fission takes place with rather heavy elements and fusion with rather light ones so creating a balanced reaction is going to be tricky....   

       My only critisim (and I think it is an interesting one) is that the propsal creates a parrallel between atomic energy and petroleum --- in the end we are going to run out of fuel. [What do you think comes after atomic energy?]   

       With regards to getting something for nothing. I posted a note about a "gravity well" which broke the 2nd law of thermodynamics... this situation is not quite the same --- eventually we will run out of mass. It is at that point that the thermodynamic laws as we know them will break down since these laws cannot be applied to the universe itself.
madness, Dec 23 2004

       If the Bering Strait was dammed and cold Arctic water was pumped out and more warm Atlantic water was pulled to melt the North Pole, would the earth heat up faster or slower? If we were able to freeze more water by transporting it to freezing areas, therby increasing our ice mass, would the earth heat up faster or slower?
mensmaximus, Dec 23 2004

       //If the Bering Strait was damned //

I'll send a letter to the Pope right away and see if he can arrange it.
DrBob, Dec 23 2004

       [ldischler], there are a couple of problems with your suggestion, besides that under the conditions found in the core of the Sun, not much is likely to interfere with the fusions going on. First is the fact that the core is nearly 700,000 kilometers from the surface, so just GETTING your poison through the intervening matter isn't so simple (not to mention that the core doesn't generally exchange much matter with its surroundings). Second, turning off the hydrogen fusions will just cause the Sun to enter the Red Giant stage early! See, when too much helium "ash" accumulates in the core, THAT suffices as a poison to interfere with the normal rate of hydrogen fusion. BUT, always remember that the Sun's energy output is what keeps its radius at nearly 700,000km. A lesser energy production means that the Sun's Gravity -- due to its mass -- can start to shrink the Sun, and this causes compression-heating at the core. That's why helium fusion will eventually start to happen! That's also why the only good way to reduce the rate of hydrogen fusion is in conjuction with lessening the mass of the Sun. Because then that extra gravitational compression WON'T happen!   

       [madness], Oh, yes, indeed, there appears to be a finite supply of energy sources in the observed Universe. But we can make do with hydrogen fusion for perhaps long enough to discover something better (total conversion, anyone?). Also, I recently learned that General Relativity, our best description of the large-scale workings of the Universe, does NOT explicitly Conserve Energy "globally" (only "locally"). So, this may either be something that gets "fixed" in the future, when G.R. gets merged with Quantum Mechanics, or we will actually end up with genuine perpetual-motion machines! To be determined...but the more trillions of years we can arrange for such researches, the better! I heartily recommend you (and everyone else) hunt up a short story by Isaac Asimov, "The Last Question". He said it was his personal favorite of all he wrote.
Vernon, Dec 23 2004

       Didn't he make that movie i-Robot... I am gonna see Blade next I reckon. What movie theatre is it showing at :)P   

       [why do we need to worry about keeping Earth habitable? ] Ummm I think it is obvious... at the end of the day there won't be any more pastures new....
madness, Dec 23 2004

       Throw in some interesting characters, create a little suspense, etc. here and there and this idea could itself be a sci-fi novella. (Perhaps someone from 'Destroy the Sun' could secretly put up their own reflectors to take out one of the bracketing magnets with the intended result being a solar comet?)
Zimmy, Dec 23 2004

       You've added to this idea since I last looked at it, haven't you?   

       Yes. He did.
DesertFox, Dec 23 2004

       //Didn't he make that movie i-Robot//   

       You had better be trolling, or I'm gonna find out where you live.
Detly, Dec 24 2004

       ["The Last Question"] I read it --- and remembered I had read it already.   

       If the universe is a big pizza hut pizza pie how much bigger is the cheese pizza compared to the super supreme? Entropy implies that the universe is expanding and transforming from a super supreme into a cheese pizza.   

       Decreasing entropy implies making a super supreme out of a cheese pizza --- making the universe smaller.
madness, Dec 24 2004

       [madness], No, to decrease Entropy does not automatically mean the Universe must grow smaller. It DOES mean that the energy contained in the Universe must grow more concentrated, but the overall volume of the Space of the Universe can remain the same or even keep expanding.
Vernon, Dec 24 2004

       [Dr. Bob] Any answer from the Pope yet? I just want to know if it's still safe to buy Pacific Salmon.
Zimmy, Dec 30 2004

       All I have to say is that you must've done a lot of research and taken about an hour to write that explanation.
hobbitcoat, Jun 17 2005

       [hobbitcoat], no special research was required. Just years of always reading stuff like "Scientific American". And remembering. Now I admit that writing stuff can take a while, but at least I'm a touch-typist, which helps.
Vernon, Jun 17 2005

       /an element that would poison the fusion reactions./ - this is a nifty idea. I imagine this would be analogous to the carbon rods used to dampen fission reactions. My science is too poor to imagine what sort of substance this might be. I think it would probably take a large amount of it. You would need to introduce it gradually, as a planetary sized lump would have gravitational cosequences as it came through the solar system en route to the sun.   

       I envision an extraterrestral launch pad which consumes a planetoid of the requisite material and launches it lump by lump at the sun. This stuff would be moving fast enough that it could punch down thru the 700,000 K to get to the party. And be the turd in the punchbowl!
bungston, Jun 17 2005

       What about the reverse of this idea? Is there anything we could do to make stars explode, perhaps turning them into balck holes? You could make a giant stellar golf course.
finrod, Jun 17 2005

       Sorry, that darn Alice/Bob blindness kicked in again and my eyes just slid over the whole thing.   

       Someone better write this one on a stone tablet somewhere, so the cockroaches get it when they Take Over the World.
"Hi! Technically it was never our problem, but we were thinking, and here's something you guys might want to consider after we've gone..."
"P.S. Look out for the ants, they've got Big Plans."
"P.P.S. Also the lungfish. Don't trust them, either."
moomintroll, Jun 17 2005

       I swear I read this as "Paving he Sun" earlier.   

       As I read the idea, I was trying to construe the process as a paving.
fishboner, May 31 2013

       //Suggestion: need a "Save the World" category//   

theircompetitor, May 31 2013

       We don't need to save the sun, saving the sunlight would be more handy.   

       Either start saving it now (which the biosphere (what's left of it) is already doing for us) or just wait and then make FTL drives to collect the sunlight which has already been beamed out there.
not_morrison_rm, Jun 01 2013


back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle