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Comment by naveen99 | Hacker News Reader

the earth has elements that were formed in previous generation of stars. I wonder if the sun is also not a first generation star.

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The sun is estimated to have formed less than 5B years ago. The universe is roughly 13B and change years old, and the first stars started forming only 100M years after the beginning. There's absolutely no way it could be a first generation star.

The first-generation stars are imagined to have lasted only a few million years before going supernova and (because of their size) becoming black holes.

We can never be certain, of course, because they are all long gone. Like, 13 billion years gone. The James Webb telescope is hoped to see back nearly that far back, but not likely near enough to catch any of them.

The entire solar system precipitated out of the same interstellar dust, which has to contain the remnants of previous generations of stars, including collided neutron stars, in order for there to be heavy elements beyond iron.

We get heavier elements from supernovas, ergo, I don't see how neutron star collisions are a requirement to explain our composition. Citation?

Not all heavier elements are from supernovae. This is known as nucleosynthesis ( https://en.wikipedia.org/wiki/Nucleosynthesis ) and there are a number of different origins of elements. Exploding massive stars really only get you up to Rb (atomic number 37).

I guess my habit of listening to PBS SpaceTime is paying off. https://iopscience.iop.org/article/10.3847/2041-8213/ac26c6

Current belief is many elements can’t be made by supernova and would require neutron star collisions

It definitely is not a first generation star. It's only about 5 billion years old, while the universe is almost 14 billion years old.

Not only does earth have elements formed in older stars, so do all the planets in the solar system and our own sun.

It very surely isn't. It formed 4.5e9 years ago, while there are stars that formed only hundreds of millions years after the big bang in the milkyway.

The sun is absolutely not a first generation star. It is approximately one third the current best estimated age of the universe (4.6B vs 13.8B years).

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