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A few basic questions I hope someone can help me with!
Watching a HISTORY CHANNEL show last night, the narrator was speaking about how "we are made of stardust" etc ... How every element that makes up planets and people were formed in stars via fusion into heavier and more complicated atoms.
Firstly, he mis-spoke, right?
Hydrogen wasn't formed in stars, hydrogen is the simplest atom that resulted from (or at least already existed after) the Big Bang ... Hydrogen needn't be created in stars then ejected into the Universe, it just formed when the Universe cooled down enough to become "matter"
I think I'm right there?
----> But my main question is: How many "generations" of stars (the first star forming, fusing heavy atoms, exploding or dying ... the second "generation" of stars forming out of the first stars' debris and cooking up more atoms ... dying and ejecting its debris ... etc) are needed before the Universe has all the necessary complex atoms to make planets and people?
If the universe is 14 billion years old, and our Sun or earth is already 4 billion years old (but has a life expectancy of 10+ billion years) ...
How many generations of stars have lived and died to make us? It can't be many.
And since the debris cannot be "traveling" very fast, if it's slow enough to be captured by mere gravity into lumps to become new suns and planets ...
----> How far away can the debris have traveled from? Not horribly far, on a cosmic scale? (For instance, can we contain atoms formed in another galaxy's stars? or are they too far away?)
And, to ask the dumbest of questions: I hear often that to look at a star 5 billion light years away means we're seeing it as it was 5 billion years ago (when its light left it) ... So that same star has been evolving and changing for 5 billion years, what we see as "the early structures of the universe" are long ago gone?
----> Are there then possible structures and forms of our existing universe we can by definition know nothing about? If there's dark matter and energy, and it's 5 billion years away, can it be undergoing weird changes that dark matter and energy isn't undergoing anywhere nearby where we can ever hope to study it?
Could there be some other, different sort of space-time at work far away, that suddenly reaches us and changes everything?
I don't mean in the "It's Sci-Fi, write any crap you imagine" way, but in a valid "Here's where our Scientific knowledge just cannot be known to hold true" way?
Anyway ... any answers or insights will be a help, and I apologize if I'm asking stoopidity!
Watching a HISTORY CHANNEL show last night, the narrator was speaking about how "we are made of stardust" etc ... How every element that makes up planets and people were formed in stars via fusion into heavier and more complicated atoms.
Firstly, he mis-spoke, right?
Hydrogen wasn't formed in stars, hydrogen is the simplest atom that resulted from (or at least already existed after) the Big Bang ... Hydrogen needn't be created in stars then ejected into the Universe, it just formed when the Universe cooled down enough to become "matter"
I think I'm right there?
----> But my main question is: How many "generations" of stars (the first star forming, fusing heavy atoms, exploding or dying ... the second "generation" of stars forming out of the first stars' debris and cooking up more atoms ... dying and ejecting its debris ... etc) are needed before the Universe has all the necessary complex atoms to make planets and people?
If the universe is 14 billion years old, and our Sun or earth is already 4 billion years old (but has a life expectancy of 10+ billion years) ...
How many generations of stars have lived and died to make us? It can't be many.
And since the debris cannot be "traveling" very fast, if it's slow enough to be captured by mere gravity into lumps to become new suns and planets ...
----> How far away can the debris have traveled from? Not horribly far, on a cosmic scale? (For instance, can we contain atoms formed in another galaxy's stars? or are they too far away?)
And, to ask the dumbest of questions: I hear often that to look at a star 5 billion light years away means we're seeing it as it was 5 billion years ago (when its light left it) ... So that same star has been evolving and changing for 5 billion years, what we see as "the early structures of the universe" are long ago gone?
----> Are there then possible structures and forms of our existing universe we can by definition know nothing about? If there's dark matter and energy, and it's 5 billion years away, can it be undergoing weird changes that dark matter and energy isn't undergoing anywhere nearby where we can ever hope to study it?
Could there be some other, different sort of space-time at work far away, that suddenly reaches us and changes everything?
I don't mean in the "It's Sci-Fi, write any crap you imagine" way, but in a valid "Here's where our Scientific knowledge just cannot be known to hold true" way?
Anyway ... any answers or insights will be a help, and I apologize if I'm asking stoopidity!