Editing Talk:1944: The End of the Rainbow

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I'm pretty sure the numbers are completly wrong, 0.3 parts per trillion probably comes from [https://www.quora.com/Is-there-any-gold-in-the-sun-If-so-how-much-gold-could-be-contained-in-it here] (because the same article was used as a reference at some point in the history of the explanation), but I think this is the ratio of atoms, not mass. The answer on quora uses the same value of 0.3 parts per trillion but instead of 6*10^17 kg of gold, deduces from that number that there is 10^20 kg of golds. One atom of gold is ~195 times as heavy as one atom of hydrogen, and since the Sun is mostly hydrogen and also some heavier elements, the mass of gold over the average mass of atoms in the Sun should be a little below 195. The ratio between 10^20 and 6*10^17 is 167.
 
I'm pretty sure the numbers are completly wrong, 0.3 parts per trillion probably comes from [https://www.quora.com/Is-there-any-gold-in-the-sun-If-so-how-much-gold-could-be-contained-in-it here] (because the same article was used as a reference at some point in the history of the explanation), but I think this is the ratio of atoms, not mass. The answer on quora uses the same value of 0.3 parts per trillion but instead of 6*10^17 kg of gold, deduces from that number that there is 10^20 kg of golds. One atom of gold is ~195 times as heavy as one atom of hydrogen, and since the Sun is mostly hydrogen and also some heavier elements, the mass of gold over the average mass of atoms in the Sun should be a little below 195. The ratio between 10^20 and 6*10^17 is 167.
 
There's still a ratio of 20 between that value (10^20 kg) of the mass of gold on the sun and the one [https://www.wolframalpha.com/input/?i=(abundance+gold+sun)+*+(mass+sun) from wolframalpha], and I'm quite expecting Randall to have used the latter, which is of 2 [https://en.wikipedia.org/wiki/Names_of_large_numbers quintillion] tons of gold on the Sun, IE "quintillions of tons" as expressed by Megan. Maybe that value is wrong, but I think it should be mentionned to show that Randall probably didn't just make up a number. [[Special:Contributions/141.101.88.16|141.101.88.16]] 17:42, 19 January 2018 (UTC)
 
There's still a ratio of 20 between that value (10^20 kg) of the mass of gold on the sun and the one [https://www.wolframalpha.com/input/?i=(abundance+gold+sun)+*+(mass+sun) from wolframalpha], and I'm quite expecting Randall to have used the latter, which is of 2 [https://en.wikipedia.org/wiki/Names_of_large_numbers quintillion] tons of gold on the Sun, IE "quintillions of tons" as expressed by Megan. Maybe that value is wrong, but I think it should be mentionned to show that Randall probably didn't just make up a number. [[Special:Contributions/141.101.88.16|141.101.88.16]] 17:42, 19 January 2018 (UTC)
:I've attempted to get to the bottom of this - Wikipedia gives limited sources.  A search for [[https://www.wolframalpha.com/input/?i=(abundance+gold+sun)|(abundance+gold+sun) on WolframAlpha]] gives 10^-7% by mass, but again, their references don't seem to support that (at least from a brief scan).  Quora cites [[http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1968PASAu...1..133A&data_type=PDF_HIGH&filetype=.pdf&type=PRINTER&whole_paper=YES|a 1968 paper] but I can't read that very well - I've attempted to analyse their data but I'm afraid I've been unable to determine how Quora reached their ".3 parts per trillion" from that paper.  (I might drag out some textbooks and try again later.)  In any case these two numbers are in wild disagreement, even if we assume Quora meant atomic ratios and multiply their number by 197 (atomic mass of gold; gold only has one stable isotope).
 
:As mentioned, WolframAlpha's number gives 2.0x10^21 kg, or 2 quintillion tonnes, whereas Quora's gives 6.0x10^17 kg, or 0.0006 quintillion tonnes (0.12 quintillion tonnes if we mutiply by 197).
 
:Of course, none of these results are small!  I'd be happy with a pot of gold of even half a quadrillion tonnes. [[User:Cosmogoblin|Cosmogoblin]] ([[User talk:Cosmogoblin|talk]]) 20:26, 19 January 2018 (UTC)
 
  
 
How can 'more than' be off by a factor of anything, given that it's non-specific? It could be 'fractionally more than' or 'a thousand times more than'.[[Special:Contributions/162.158.111.204|162.158.111.204]] 18:07, 19 January 2018 (UTC)
 
How can 'more than' be off by a factor of anything, given that it's non-specific? It could be 'fractionally more than' or 'a thousand times more than'.[[Special:Contributions/162.158.111.204|162.158.111.204]] 18:07, 19 January 2018 (UTC)

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