On the Origin of Gold; Golden Globe Award (APOD 18 May 2008)

[iampete]

Just how reasonable is this conjecture? (http://antwrp.gsfc.nasa.gov/apod/ap080518.html)

On several threads here, it has been opined and demonstrated (at least at a conceptual level and also with references elsewhere) that the likelihood of stellar collisions during galaxy collisions is miniscule. I would expect that stellar collisions in a "stable" galaxy would be even less likely. Going further, it seems reasonable to expect that the likelihood of a neutron star colliding with a "regular" star is much smaller still, and the likelihood of two neutron stars colliding is somewhere between vanishingly small and no way in heck. And the likelihood of stellar collisions of extra-galactic stars is probably even smaller.

Today's APOD identifies that some astronomers postulate that the formation of some elements might be due to neutron star collisions.

Is this conjecture just hanging out there by itself somewhere and shown on APOD because it makes pretty pictures, or has it been evaluated by other astronomers who may have played with probability numbers to see if it's a reasonably likely explanation?

Edit: Two of the links on this APOD didn't work for me. If this is explained, could someone post a direct URL?

[Qev]

As I understand it, collisions between unbound stars (of any sort) are very rare events, simply due to the enormous probabilities against them. However, collisions between bound neutron stars (ie. those in orbit around each other) are practically inevitable over time, as gravitational radiation steals angular momentum out of the system, causing them to spiral in towards each other.

[iampete]

Thanks, Qev.

Apparently, the recent reading about the colliding galaxies and the miniscule stellar collision likelihoods therein totally blanked the "bound stars" scenario from my alleged brain.

Also, for whatever it's worth, one of the non-working links (Miller at UMd) started working again while the utube one still gives me the "The URL contained a malformed video ID" message.

[Case]

The YouTube [link] still gives me the "The URL contained a malformed video ID" message.

Again sloppy code in the webpage: missing end-quote character (").

www.youtube.com/watch?v=HfDDI_SCarw is the correct one.

[iampete]

Thanks, Case, for the correct link.

[kovil]

"Going further, it seems reasonable to expect that the likelihood of a neutron star colliding with a "regular" star is much smaller still, and the likelihood of two neutron stars colliding is somewhere between vanishingly small and no way in heck."

Agreed ! With major size mass-bodies having extremely small collision numbers, why would anyone in their right mind propose that neutron star collisions could possible account for the abundance of gold on Earth.

the answer is; they don't know how gold forms and are grasping at idea straws to see how long they are, and if someone else will get an inspiration into the truth of the matter.

I too have wondered about the abundance of heavy elements on Earth and if local nova production scattering in our neighborhood could account by interstellar cloud condensations for Earth's constitution.

It seems more likely that our own Sun went nova itself 4.5 billion years ago and the Z-pinch structure to its cause of nova is what determined the solar systems orbital plane orientation, and the mass fractionated sorted by atomic weight orientation within the Sun before nova is what is responsible for the outermost planets being gas giants and the innermost planets being the heavy metal planets, as the metals were lower in the Sun and the lighter elements more toward the surface so they went further out in the nova. Our Sun didn't go supernova, it was a small explosion casting off of material, an electrical bifurcation (multifurcation) to lower the electrical stress on its surface, as the local intergalactic current flow heated it up way to hot, possibly like Rigel is experiencing now (our present observing spacetime frame, not the absolute spacetime frame for Rigel itself in its realtime, Rigel could have novaed (multifurcationed) already but we don't see it yet).

[apodman]

According to a Jeopardy question a couple of years ago, all the gold ever extracted from the earth adds up to less than a cubic mile.

[Sputnick]

http://antwrp.gsfc.nasa.gov/apod/astropix.html May 18 - oops

corrected courtesy Orin to http://apod.nasa.gov/apod/ap080518.html

If they weren't afraid of the media The Big Chickens at APOD could have called today's picture The Golden Globe Awards. Cluck Cluck Cluck.

[orin stepanek]

http://apod.nasa.gov/apod/ap080518.html ?
Orin

[William Roeder]

According to a Jeopardy question a couple of years ago, all the gold ever extracted from the earth adds up to less than a cubic mile.

Actually it would measure 25 meters per side.

[BMAONE23]

From WIKI
http://en.wikipedia.org/wiki/Gold#cite_ ... eetlinks-9

"Gold in antiquity was relatively easy to obtain Geologically; however, 75% of all gold ever produced has been extracted since 1910. It has been estimated that all the gold in the world that has ever been refined would form a single cube 20 m (66 ft) on a side (equivalent to 8000 m³)."

[Sputnick]

Thanks Orin - how mistakes happen is anyone's guess.

[orin stepanek]

Thanks Orin - how mistakes happen is anyone's guess.

No problem! I made a lot of errors myself along the way. Probably still do.
Orin

[orin stepanek]

Am I missing something here? If it takes a collision of neutron stars to create gold and there is gold on Earth; therefore the solar system must be a product of this collision including the Sun and the Earth? Or did the solar system wander into the path of debris left over from this collision?
Orin

[henk21cm]

If it takes a collision of neutron stars to create gold and there is gold on Earth; therefore the solar system must be a product of this collision including the Sun and the Earth? Or did the solar system wander into the path of debris left over from this collision?

Two options.

1. Two neutron stars collide. The debris and shock wave creates disturbances in the interstellar gas, which starts to clotter. Sun and planets form.
2. A star imploded, when it started to produce iron and trans-iron elements by means of fusion. Similar to an imploding cathode ray tube, after a short while this implosion transforms into an explosion and the shock waves of this explosion create disturbances in the interstellar gas, which starts to clotter. Sun and planets form.

What tickles the mind is not the mere fact that there is Au on earth, but that there is an awful lot more Pb on earth, which should be even more difficult to create by nuclear fusion. Elements like U and Pu are even more unlikely, nevertheless they exist.

[iamlucky13]

If I'm reading the caption right, not all of the gold in the universe would come from neutron star collisions according to this theory. Some would be due to more "conventional" supernovae, but the amount of gold is apparently higher than theory for this predicts.

Orin, our solar system formed partially from the debris of 1st and 2nd generation stars that had already burned out and expelled planetary nebulae, or even undergone novae or supernovae. These events would have happened before our solar system formed, or perhaps even initiated the formation of it.

[kovil]

Currently we don't know how heavy elements form, but there are a couple of theories, and the newest isn't accepted by the old folks yet.

1. The so-called standard solar model has fusion in the solar interior making elements up to iron, heavier than that it takes a nova or supernova to produce them, and the Sun and the solar system condensed from interstellar gas.

2. The Oliver Manuel Theory has the Sun being a collapsed nova remnant with some material falling back onto its surface, and the ejecta as being what caused our solar system. Where the Sun came from initially he doesn't hypothesize, but there is overwhelming new evidence (the last 40 years and 5 years) that our Sun has its internal mass sorted by atomic weight with the lightest elements at the surface and only 3% of its power output derived from fusion reactions, with neutron-neutron repulsion in the core being the major source of internal heat, not fusion reactions. Professor Manuel likewise thinks a nova will make heavy elements.

http://www.omatumr.com/PapersArxiv.html

I tend to think that our material elements came from close by rather than far away, so the idea our Sun went nova by an electrical activity 4.5 Billion years ago much more successfully accounts for our solar system formation than a slow gravitational accumulation over a long period of time, as computer models have not been able to make planets form in a flat plane nor in discrete lumps within that plane.
The electrical Z-Pinch forms a flat equatorial disk of explosive material dispersed by its basic nature, and that is exactly what we observe.

[orin stepanek]

If I'm reading the caption right, not all of the gold in the universe would come from neutron star collisions according to this theory. Some would be due to more "conventional" supernovae, but the amount of gold is apparently higher than theory for this predicts.

Orin, our solar system formed partially from the debris of 1st and 2nd generation stars that had already burned out and expelled planetary nebulae, or even undergone novae or supernovae. These events would have happened before our solar system formed, or perhaps even initiated the formation of it.

I figured that old Sol may be a 2nd or 3rd generation star; but never thought of it as being formed from a neutron star collision's debris field. I guess it's building blocks had to come from somewhere! Could it be that the sun and solar system may have happened to come into the clutter that the super nova left behind; might explain all the junk orbiting the sun.
Orin

[astrolabe]

Hello All,

Gold that appeared and was subsequently mined in veins would indicate to me that it was interspersed as a liquid within molten rock and then cooled. Sometimes it was discovered because a portion of the vein was probably exposed by erosion.

As an .added thought, if gold was "collected" as the early solar system traveled through neutron star remnants one would think that being the heavy element that it is it would sink in a molten environment. So there's more than likely undiscovered gold at greater depths in the Earth's crust.

It also may have been that the faster rotation of the early Earth centrifugally kept the liquid gold suspended closer to the surface

[iampete]

It also may have been that the faster rotation of the early Earth centrifugally kept the liquid gold suspended closer to the surface

That would have been one heck of a spin rate.

Is there any basis for postulating a spin rate several orders of magnitude higher than the current one? I've tried a very cursory search and have turned up nothing.

[Dr. Skeptic]

The deposition of Au in the Earth's crust has more to do with where it collects and how it likes to solidify, almost all Au is found solidified in veins formed at a juncture where quartz has extruded into granite – that is unless it has been eroded out.

[iamlucky13]

I figured that old Sol may be a 2nd or 3rd generation star; but never thought of it as being formed from a neutron star collision's debris field. I guess it's building blocks had to come from somewhere! Could it be that the sun and solar system may have happened to come into the clutter that the super nova left behind; might explain all the junk orbiting the sun.
Orin

I figured actually debris from multiple supernovae and possible neutron star mergers.

Regarding gold lodes, according to wikipedia, this is owed partially to its generally non-reactive properties of gold. Materials surrounding may be easily oxidized and carried away over the millenia, leaving tiny bits of gold. Because it is so maleable, these bits can cold-weld together, forming flakes and nuggets. There's also reserach suggesting that certain microbes may accellerate this process.

http://en.wikipedia.org/wiki/Gold#Occurrence

[henk21cm]

That would have been one heck of a spin rate.

How fast? Lets try to counterbalance the centrifugal force by the equitorial gravitational force.

ω² R = g ................................ (Eq. 1)

with g the acceleration of gravity. With ω = 2 π/T this leads with (1) to:

T ≅ 2 √ (R)

if we approximate π² by g. T is de axial rotation period of the earth. With R = 6.5E6 m, T ≅ 5100 s: 1h 25m

There are indications that the earth has been spinning faster than now: 1 day lasted approximatedly 10h. Centrifugal forces in that case will be considerably lower: about 50 times lower.

[iampete]

. . . T ≅ 5100 s: 1h 25m . . .

You're correct. I somehow messed up and calculated ~8 minutes originally.

. . . There are indications that the earth has been spinning faster than now: 1 day lasted approximatedly 10h. . .

Can you provide a link? My (admittedly very cursory) search has come up with a lowest value of ~20 hours based on sedimentary rock layering evidence.

[Chris Peterson]

Currently we don't know how heavy elements form

Actually, we have a very good idea about mechanisms that produce heavy elements, and they are well supported by theory and observation. This issue with gold relates to another mechanism (in parallel with better understood mechanisms) that helps explain the actual observed abundance.

2. The Oliver Manuel Theory has the Sun being a collapsed nova remnant with some material falling back onto its surface, and the ejecta as being what caused our solar system. Where the Sun came from initially he doesn't hypothesize, but there is overwhelming new evidence (the last 40 years and 5 years) that our Sun has its internal mass sorted by atomic weight with the lightest elements at the surface and only 3% of its power output derived from fusion reactions...

To be more precise, there is virtually no evidence of this, and there isn't any part of Manuel's theory that isn't better explained by other theories. It is Manuel's basic lack of respect for (or understanding of) the scientific method that has resulted in him being considered a crackpot by virtually the entire scientific community.