How long would it take the Universe to generate an Earth-like chemistry?

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Discussion Overview

The discussion centers on the timeframe required for the universe to generate an Earth-like chemistry, focusing on the formation and distribution of elements necessary for life. Participants explore the implications of stellar processes, supernovae, and the availability of heavier elements over cosmic time scales.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants propose that the minimal time needed for the generation of elements necessary for life could be less than 2 billion years, considering the life spans of early stars and the time required for material to disperse and coalesce.
  • Others argue that defining a specific timeframe is challenging due to the lack of a clear threshold for the amount of heavier elements required for life, raising questions about the prevalence of solar systems at different stages of development.
  • A suggestion is made to approach the discussion from the perspective of star generations, considering the contributions of second and third generation stars to the chemical makeup of planets.
  • Participants note that the lack of sharp resolution on the timing of element generation is expected, given the complexities involved in stellar explosions and the subsequent formation of planets.
  • There is mention of CHONPS as essential elements for life, but also recognition that many other trace elements are necessary, complicating the understanding of what is required and in what amounts.
  • Some participants express skepticism about the necessity of certain trace elements, like iron, suggesting that alternatives exist in biological systems, which adds to the complexity of the discussion.

Areas of Agreement / Disagreement

Participants generally agree that determining a precise timeframe for the generation of Earth-like chemistry is complex and lacks consensus. Multiple competing views remain regarding the necessary elements and the processes involved in their formation.

Contextual Notes

Limitations include the dependence on definitions of "Earth-like chemistry," the variability in stellar lifespans, and the unresolved nature of how much of each element is truly necessary for life.

BillTre
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Our planet (Earth) has a wide variety of different elements, which at some time had to be generated (presumably in stars) and distributed through space to new forming planets (like ours), when the stars exploded.
What is the minimal amount of time needed for this to happen?

It has often been hypothesized that many different elements were required for chemically based life (at least like what we are familiar with) to form. I am interested in limits that the availability of a varied chemistry could have hadon an earlier generation of life.
If we take the age of the universe as about 14 billion years, and the age of the Earth as about 4.5 billion years, the universe would have been about 9.5 billion years old.
What are the life spans of early exploding stars compared with that time?
 
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I think it's going to be hard to say without some idea of how much heavier elements is enough.
As long as one just needs any amount whatsoever - First stars started to form within the first billion years, and the most massive of those died after a few million. Add an extra few or a few dozen million for the material to disperse, mix, and start coalescing again. Probably a good bet to say less than 2 billion years overall. The longer one waits, the higher the concentrations, on average.
 
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I agree with @Bandersnatch that it's hard to pit an exact date on it because there's not a hard edge. Solar systems half as prevelent as today? One percent? One in a million? One per galaxy? Where do you draw the line?

The time scale for supernovae is a few million years. The time scale for planetary system formation is a few tens of millions. The mixing time is probably a hundred million years or so, but mixing doesn't have to be complete.
 
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Would it makes sense to approach this from a star generations point of view instead of a regular time frame? For example numerous 2nd generation stars and a handful of 3rd generation stars dieing to produce the required chemical elements perhaps? However long that may take?
 
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Thanks for the responses.

A lack of sharp resolution on the when this might have occurred is not surprising to me.

I suppose that getting enough stars to blow out the larger atoms they generate and then having that come together with some reasonable amount of heavier atoms (as some have said) could prolong how long it might take to make planets with higher atomic weights like earth.
Perhaps a lot faster where there were a lot of super big early stars (if such an area existed).
 
CHONPS are often cited as the elements that compose most of Earth's living matter.
However, there are 50 some elements found in (needed?) small amounts for modern biological functioning, due to requirements for metals and other things for catalysis (as in enzymes).
Its not easy to figure out what among all this is really needed in what amounts.
 
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What trace elements are necessary is going to lead us down the path of fruitless speculation. Is iron required? Probably not, as there are bloods that use alternatives, like copper, vanadium, and arguably magnesium. I'm not sure what a parade of counter-factuals tells us.
 
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Yeah, its kind of a mess to think about.
Fe is really common in a lot of enzymes, but as you say, it can be replaced in many cases.
 

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