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0 pointsgraycat4y ago0 comments

> we are just among the first of civilizations ever,

Well maybe could say "one of":

We recall that the big bang was ~14 billion years ago.

Our solar system was made ~5 billion years ago (very rough arithmetic) out of the results of an exploded star. The star may have exploded ~7 billion years ago. In that case it may have been a first generation, hydrogen star and took ~6 billion years to form, make heavy elements, and explode (and make more heavy elements).

So, that makes our star a second generation star and our solar system, from an exploded first generation star, one of the first.

If all that is true, then, okay, "we are just among the first of civilizations ever".

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mcswell4y ago

IIRC (it's been a long time), first generation stars were very low in "metals" (which term astronomers use to mean any element heaver than helium), and what they did have was mostly (maybe entirely) lithium. They may not have had any planets, or if they did, the planets were pure gas (hydrogen and helium). Thus no life, much less intelligent life.

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