Friday June 21, 2019
Book 20: Sergeant In Motion — Prologue: Time For A Brief History

The "building blocks of life" is a phrase ordinarily taken to mean elements beyond the primordial hydrogen and helium—things like oxygen, nitrogen, and carbon—but for life as we currently know it, those blocks must also include much heavier things like iron, tungsten, and iodine. Those didn't show up in useful numbers until the death of later generations of stars, but since the shockwaves of the first supernovae triggered the formation of future stellar generations, we can still give them credit for it. 

Another thing not listed in the "building blocks of life" category is a black hole, probably for "abandon hope all ye who cross the event horizon" reasons. We'll include it, though, because the supermassive black holes left behind by the first supernovae became the anchor points for galaxies. It turns out we need those. Even the far, far away ones.