Found Another (Astrophysical) Error in Science Television

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Discussion Overview

The discussion revolves around the claim made in a Science Channel episode that all atoms in the human body were manufactured inside stars. Participants explore the implications of this statement, particularly focusing on the role of hydrogen and the origins of various elements in the universe.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants question the assertion that all atoms in the body were made inside stars, particularly highlighting that hydrogen, a major component of water, is not created in stars.
  • Others propose that while hydrogen may not be made in stars, it could have been present in stars at some point, suggesting a distinction between creation and containment.
  • A participant mentions that hydrogen is composed of quarks and that it has existed since the Big Bang, implying a finite amount of hydrogen in the universe.
  • There is a suggestion that the statement about atoms being made in stars is an oversimplification that could lead to misunderstandings.
  • Some participants agree that while many atoms in the body may have been contained within stars, the original claim about their creation is misleading.
  • One participant notes that lighter elements like lithium and beryllium also have different origins, complicating the narrative about stellar creation of all body atoms.

Areas of Agreement / Disagreement

Participants express differing views on the original claim regarding the creation of atoms in stars. While there is some agreement that hydrogen's role complicates the assertion, no consensus is reached on a definitive characterization of the statement.

Contextual Notes

Participants highlight the importance of distinguishing between the creation of elements and their presence in stars, indicating that the discussion involves nuanced interpretations of astrophysical processes.

Who May Find This Useful

This discussion may be of interest to those exploring astrophysics, the origins of elements, and the implications of scientific statements in popular media.

BadBrain
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Like they're difficult to find!

(OK, so I realize I'm going out on a limb here, considering the pounding I recently took in the "The Nobel Prize in Physics 2011 goes to Saul Perlmutter Brian Schmidt and Adam Riess" thread under General Discussion in the Lounge, but, well, I'll cast caution to the wind here.)

***

Anyways, on the Science Channel's show "How the Universe Works" episode entitled "Extreme Stars", somebody said that all the atoms in your body were manufactured inside stars.

This seems, to me, to be extremely unlikely, as 80% of our bodies consists of water, each molecule of which contains two hydrogen atoms.

If hydrogen is, at least in the non-decadent stages of their lives, the primary fuel of stars, then how can the existence of hydrogen be dependent on the existence of stars, or logically precede them temporally?

This is no chicken-and-egg question, as it's a bit like saying that the existence of petroleum is dependent upon the existence of automobiles.

(I really hope I got this one right!)
 
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That's interesting, I've never thought of that. The one thing I can think of is that just because a molecule didn't undergo at least one part of the fusion cycle doesn't mean that it wasn't inside a star at one point.
 
Vorde said:
That's interesting, I've never thought of that. The one thing I can think of is that just because a molecule didn't undergo at least one part of the fusion cycle doesn't mean that it wasn't inside a star at one point.

Quite right you are!

But what I'm saying (besides the fact that I'm primarily talking about atomic hydrogen here, in addition to molecular hydrogen) is that, whether or not an atom was ever inside a star is irrelevant to whether or not the atom was MADE inside the star; as hydrogen is necessary to the existence of stars, how can one guarantee that any hydrogen atom was created inside a star, as opposed to having aided in the creation of that star?
 
But hydrogen is never made anywhere.

Hydrogen is made out of it's composite quarks, and from what I understand it hasn't been hot enough since the seconds after the Big Bang for hydrogen to naturally synthesize.

I think the point is that there was a set amount of hydrogen from the beginning of the universe. Anything slightly larger than that (i.e. Helium/Lithium) was either also made directly after the big bang (very unlikely) or made in stars via the fusion process. Anything slightly larger than that was definitely made in the fusion process. And anything much larger than that were made in novae/supernovae.

To so say the statement "everything in your body was made from stars" is incorrect because Hydrogen wasn't made in stars, is invalid because that statement by nature can't include Hydrogen in the first place! A much more valid statement might be that "a large majority of atoms in you body was contained within a star at some point in its life".

However that's not quite as catchy, so I doubt it'll take :)
 
Vorde said:
But hydrogen is never made anywhere.

Hydrogen is made out of it's composite quarks, and from what I understand it hasn't been hot enough since the seconds after the Big Bang for hydrogen to naturally synthesize.

I think the point is that there was a set amount of hydrogen from the beginning of the universe. Anything slightly larger than that (i.e. Helium/Lithium) was either also made directly after the big bang (very unlikely) or made in stars via the fusion process. Anything slightly larger than that was definitely made in the fusion process. And anything much larger than that were made in novae/supernovae.

To so say the statement "everything in your body was made from stars" is incorrect because Hydrogen wasn't made in stars, is invalid because that statement by nature can't include Hydrogen in the first place! A much more valid statement might be that "a large majority of atoms in you body was contained within a star at some point in its life".

However that's not quite as catchy, so I doubt it'll take :)

You're right! You've stated my essential theory better than I did.

Except that I don't understand why my original statement can't include hydrogen in the first place.

Please explain.
 
I think it's just a minor mix up in wording. I wouldn't worry too much about it.
 
It's not that you're statement was wrong, It exposed a good hole in that statement.

All I was saying was that because Hydrogen can't actually be made (at least not since the Big Bang), the statement [that all the atoms in our body were made in stars] was less of an incorrect statement, and more of an oversimplification that led to mistakes.
 
Vorde said:
It's not that you're statement was wrong, It exposed a good hole in that statement.

All I was saying was that because Hydrogen can't actually be made (at least not since the Big Bang), the statement [that all the atoms in our body were made in stars] was less of an incorrect statement, and more of an oversimplification that led to mistakes.

Gotchya! Agreed!
 
  • #10
When stars 'die' [e.g., supernova], they expel their outer envelope - which still contains a large amount of 'unburnt' hydrogen. There also remains vast quantities of 'virgin' [primordial] hydrogen in the universe. Water, however, is also composed of oxygen and virtully all oxygen atoms are manufactured in stars.
 
  • #11
Chronos said:
When stars 'die' [e.g., supernova], they expel their outer envelope - which still contains a large amount of 'unburnt' hydrogen. There also remains vast quantities of 'virgin' [primordial] hydrogen in the universe. Water, however, is also composed of oxygen and virtully all oxygen atoms are manufactured in stars.

Correct you are! But hydrogen, two of whose atoms are a component of water along with each oxygen atom, is not made in stars, which still makes the talking-head scientist's statement wrong!
 
  • #12
BadBrain said:
Anyways, on the Science Channel's show "How the Universe Works" episode entitled "Extreme Stars", somebody said that all the atoms in your body were manufactured inside stars.

This seems, to me, to be extremely unlikely, as 80% of our bodies consists of water, each molecule of which contains two hydrogen atoms.

Yup. I think you are correct. Also some of the lighter elements such as lithum and beryllium come about through cosmic ray spallation.
 
  • #13
I think the point is not a molecule in your body does not contain atoms manufactured in stars. Perhaps that is a more accurate characterization.
 
  • #14
Chronos said:
I think the point is not a molecule in your body does not contain atoms manufactured in stars. Perhaps that is a more accurate characterization.

I hadn't thought about it that way and I find that to be a very helpful way to look at it. Thanks for that insight.
 

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