Creating Elements after BB: Where did the Supernova's Go?(Vanity)

We know the masses and general composition of the four inner (rocky) planets in our solar system, and from basic chemistry, we know the number of atoms in a gram of any material.

Multiplying Avogadro's number x the mass of these four planets, dividing by a weighted average atomic weight for the materials in each planet, we get about 3 x 10^ 50 heavy nuclei produced since creation/the big bang.

Take your pick, that's the number of atomic nuclei we have to account for. Another 5 x 10^50 heavy nuclei are probably in the rocky cores of the Jovian planets, though core weights are very difficult to estimate. Astronomers estimate that icy comets and dust in the Oort cloud may double the mass of the inner eight planets.

So, in this little bitty solar system, we have (at least) 8 x 10^50 atomic nuclei that were created somehow.

Convention theory holds that these were formed inside supernova's, were ejected into space, captured by nearby stellar clouds, condensed into a star large enough to go supernova, went through another supernova and fused into higher level elements, and got ejected into space, captured by another gas cloud ... etc. Finally, they were captured by our proto-sun in our region of space, and, under gravity condensed into a spinning cloud that in turn, condensed further into rings, then these rings congealed into planets.

We see this process going on, and supernova's seem to occur in visible galaxies, about once every 50-100 years. Dust clouds ejected from supernova's in our galaxy within the last 1000 years are visible - clearly the conventional wisdom works.

Further, conventional teaching holds that the earth has been solid for 4.6 some-odd billion years - solid rocks in Canada and Australia test out that old, and are "untouched" by subsequent supernovas and catastrophic melting. The moon is a little older than those 4.5 billion years, and theory holds it was formed from a near-miss of an asteroid collision: was ejected into space as a large mass of earth's crust, then congealed into a sphere. So, we can prove from the moon and Canada that "new" matter has NOT been formed in the solar system in any quantity since at least 6-8 billion years ago.

There aren't enough supernova's, not enough nearby stars, and not enough time between the big bang (14.5 billion years ago) and the formation of the solid planet dust rings (6 some-odd billions of years ago) for the elements to have been created.

14.5 billion years (BB) - 6 billion years (solids as dust found orbiting a proto-sun in our solar system) = 8.5 billion years.

We are told that our sun is a second generation star, which reasonable, and that it will burn for another 4-6 billion years. Again, reasonable. The 100 closest stars are mostly much smaller than the sun, and most are dimmer than the sun. Sirius A, for example, is one of the few that are brighter than the sun. Distances vary of course, but most are further than 15-20 light-years. Obviously there are no supernova's nearby, and none have been nearby - or we would "see" the remnants of the supernova, and (if dark) we would have sensed the remainder as a black hole: since the black hole would distort light, radio, infrared, and microwave radiation nearby. No nearby "heavy" masses are found at all - out to some 30 light-years at least.

The wide-ranging COBE satellite surveys that were looking for minute distortions in the background microwave radiation, for example, would have sensed nearby distortions from near-earth black holes.

8 x 10^50 atomic nuclei / 8.5 x10^9 years /31.5 x10^6 seconds per year = 3 x 10^33 atoms ejected nearby supernova's per second, traveling through space for thousands of light-years at speeds just a small fraction of light, and re-entering our gas cloud. The closest star cluster is only 4.5 light-years away: that dust cloud is a very small target for dust to be randomly ejected into its gravitational field in time to get condensed into planets.

3 x 10^33 nuclei per second sounds like a lot, and it is. But spread out over a dust cloud the size of the proto-solar system, it (almost) sounds reasonable.

But consider the requirement that ALL of these 10^50 element nuclei being ejected in one generation from a "cloud" of thousands of billions of supernova's surrounding the sun, all of these supernovas randomly but evenly spaced close enough to our dust cloud that enough of their randomly ejected elements drift our direction.

supernova's all have to gather into superstars, go through a complete lifecycle, and go supernova in very close to the same time: a particle of dust (itself many trillions of trillions of atoms - each having had to get generated itself) that comes by our future solar system's cloud too early, or too late, will not get captured by the future sun. If you assume that the average dust particle coasts through space faster (so its travel time is less getting here so there is more time for supernova's to condense and blow up) then you have to assume that the coordinated "supernova" time for all of the first generation supernovas is even more closely timed.

Ignore the need for our galaxy's dust cloud of H and He to congeal from the expanding gasses randomly ejected from the BB, for these gasses and dust particles to themselves drift into proto-stars, and for the first generation of stars (all of the first generation stars cannot be assumed to be supernova-sized of course) to go through the billions of years to change from a H-H to H-He, to Li, to Be ... up to the carbon and neon and eventually into the iron fusion changes. See, all of the heavier-than-iron atomic nuclei have to be created as well, and they can ONLY be created after the iron cycle begins: granted, there are not as many heavier-than-iron particles as the lighter ones: H, He, nitrogen, silicon, carbon, etc are much more readily found than the heavier ores. But many billons of tons of these atoms are certainly present. And every nucleus in every gram of every ton of ore, in current theory at least, has to come from its own supernova.

Granted, the universe is considered to be "smaller" the earlier that you go back in time. A smaller universe means that any given supernova is closer to the (future) position of our galaxy's (future) dust cloud, and our own sun's (future) dust cloud.

But a closer supernova still ejects 99.9 percent of its newly-formed heavy elements the wrong direction. They may form other planets, but they are useless in forming our own planet. (And, being a dweller of this planet, I can afford to be a bit selfish about not caring whether other solar systems have rocky planets or not.) Now, 99.9% of the heavy nuclei going the wrong direction is better than 99.9999 percent going the wrong direction, but it still means that many tens of thousands of supernova's are required to create our own solar system - with all of the heavy elements as we know it now.

Further, we could suppose (somehow, and no mathematical or theoretical reason exists to justify these assumptions) that the first generation of stars was somehow different that today's second generation of stars: somehow the first generation gathered tens of thousands quicker than the dust clouds we see in global clusters and nebulas, condensed into super heavy stars quicker than they do now and were much more likely to gather into super heavy dust clouds than they do now, and those newly-condensed super-heavy stars burned through their nuclear fuel cycles tens of thousands of time faster than they do now.

But, if they are correct, where did the 10^40 (?) supernova remnants go? Where are they now? They could only be 10^9 through 10^12 years old, and could not be very far from our galaxy and our sun: Why can we not find them? Our search for black holes reveals less than a few dozen heavy objects. The galaxy might have a massive black hole at its center. But even assuming that every galaxy has a black hole at center, that leaves 10^25 left to discover.

I thought Sol was a third generation star

Since a "generation" of stars can range from a few milllions to many billions of years, the concept of "second" or "third" generation isn't really applicable to the Sun. The first stars formed in the galaxy about 14 billion years ago, and the Sun was formed 4.6 billion years ago. Many "generations" of massive stars, and several generations of intermediate mass stars, contributed to the formation of the Sun.

You know, I've been puzzling and puzzling over your post, and while most of it doesn't make sense to me, I think I may have come to understand the root of your problem.

You aren't so much concerned with how the heavy elements get created, but with how they got scraped back up together again to form our solar system. Right?

If that is your concern, you may be interested in this calculation I performed almost six years ago on FR.

Here's the executive summary: given a cloud of arbitrary size that has a density as low as any found in the galaxy (one hydrogen molecule per cubic centimeter), how long does it take for the cloud to collapse completely? The answer is 700,000 years. Less than a million years. A cosmological eyeblink. Denser clouds will collapse even faster.

So if you have a supernova going off every 30 years or so, let them spread their heavy nuclei as thinly as you like across the galaxy. Gravity will have no problem collecting them up again in a very short time, whenever it has the chance. All it takes is a local density fluctuation to start the process, and the trace residues of a million supernovae--now evenly spread throughout the galaxy--will condense to form a solar system.

Another suggested Google search term: Jeans Instability

When the sun reaches it's asymptotic giant branch star phase, it will certainly create carbon, but in general you're correct. Through most of its lifetime the sun can't generate anything close to a heavy nuclei.

However, I think you're on to something. At some point in the universe's development it became too big to scatter heavy nuclei everywhere we see them now. I think your approach could be used to set limits on when the heavy nuclei must have been created and what kind of stars must have created them.

The approach I was trying to suggest was to look at the stars in the early universe to determine how many heavy nuclei they could've created. Current ideas suggest that early stars were enormous. They should have been able to get close to producing heavy nuclei before going nova and scattering heavy nuclei all over the neighbor hood.

You're much better suited to make the calculations than I am since you've had some experience calculating cross-sections for fusion reactions.

Using this approach it might be possible to set limits on the size of the stars in the early universe, possibly to determine which came first, galaxies or central galactic black holes, maybe even set limits on the size of galactic black holes, and to set limits on the time when heavy nuclei would have had to be generated to create the distribution we see now.

The penalty, of course, to assuming super-heavy stars very early in the universe is that you generate black holes (after the supernova) that tend to recapture the ejected material.

Alternate: If the superstar dust cloud mass is enough to form a black hole, and the dust cloud collapse time is as short as indicated above (< 3/4 million years) then what would prevent the black hole from forming before or during stellar evolution: at a period when all of its material would go down the hole and none be available for ejection?

We still would assume that the time, heat and pressure to go from first fusion (H + H and H - D, etc) to second generation fusion ... up to the final layer is not enough to overcome the black hole limits of gravity and distance.

The penalty, of course, to assuming super-heavy stars very early in the universe is that you generate black holes (after the supernova) that tend to recapture the ejected material.

A black hole has no more ability to recapture the ejecta than any other body of the same mass. The gravitational field is the same outside of the radius of the pre-collapse core.

Alternate: If the superstar dust cloud mass is enough to form a black hole, and the dust cloud collapse time is as short as indicated above (< 3/4 million years) then what would prevent the black hole from forming before or during stellar evolution: at a period when all of its material would go down the hole and none be available for ejection?

Newton's laws. When the core collapses, all of that gravitational potential energy is released. It can't all just "fall down the hole". Now remember, that energy is ALL being released within the center of the star, and it is going to be imparted to the surrounding mantle.

Now think about this: the thermal heat of the star, prior to core collapse, was enough to support the mantle. It wasn't falling into the core, except perhaps slowly. In a few tens of milliseconds, that energy density is exceeded by tens of orders of magnitude, and you expect the mantle to fall inwards?

That's not to say that supermassive black holes didn't form in this period. They did. There are trillions of galaxies in our Hubble volume, and many contain million-solar-mass black holes at their cores. So there might be a trillion of those within causal reach. Wow!

We still would assume that the time, heat and pressure to go from first fusion (H + H and H - D, etc) to second generation fusion ... up to the final layer is not enough to overcome the black hole limits of gravity and distance.

I didn't understand that.

Yeah - I erred.

I was thinking ahead of the problem, and got my thoughts fluxed up.

Regardless of how much mass in present, until that mass is concentrated so the escape velocity is irrelevant during any period of the first generation star until after it collapses, after the supernova.

Assume a star 10x the mass of the sun is first generation: It condenses, begins fusion, then goes through a lifecycle until the inner core is creating iron. If it goes supernova, the mass remaining in the center will be (almost certainly) to be within the Schwarzschild radius and lost to future generations, but as Phys. pointed out, that core mass is about 1/10 the mass of the original dust.

The remaining 90% of the original mass is ejected, ready for recycling. An open question is how much of that 90% that is ejected is "heavy" elements, and how much is unreacted H and He.

"...Many "generations" of massive stars, and several generations of intermediate mass stars, contributed to the formation of the Sun..."

That's as I recalled it, RadioAstronomer, and the timing seems correct.

First-Generation stars would have no planetoids, but would be the furnaces for the formation of heavier elements.

Their destruction about 8 to 9 billion years ago would then lead to the formation of new Second-Generation stars with some solids-junk possible.

Subsequent aging and destuction-reformation leads to Third-Generation stars about 4.6 billion years ago with lotsa possibilities of planetoids, and lotsa heavier elements.

I've spent the last 45 years as a Plastics Engineer, so all I can do is wonder about the possibilities. Thanks for the interesting input ............... FRegards

The weak force is the force that induces beta decay via interaction with neutrinos. A star uses the weak force to "burn" (nuclear fusion). Three processes we observe are proton-to proton fusion, helium fusion, and the carbon cycle. Here is an example of proton-to-proton fusion, which is the process our own sun uses: (two protons fuse -> via neutrino interaction one of the protons transmutes to a neutron to form deuterium -> combines with another proton to form a helium nuclei -> two helium nuclei fuse releasing alpha particles and two protons). The weak force is also necessary for the formation of the elements above iron. Due to the curve of binding energy (iron has the most tightly bound nucleus), nuclear forces within a star cannot form any element above iron in the periodic table. So it is believed that all higher elements were formed in the vast energies of supernovae. In this explosion large fluxes of energetic neutrons are produced which produce the heavier elements by nuclei bombardment. This process could not take place without neutrino involvement and the weak force.

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