The sequence of events that led to the Earth being here with us on it is kind of mind-blowing in terms of physics.
First, the nascent universe had to cool such that nucleons formed, which then became hydrogen. This matter wasn't evenly distributed. Some of it under its own weight collapsed under gravity and birthed the first stars.
It seems that shock waves in nebulae trigger star formation. This could be black holes and/or neutron stars merging, supernovae and possibly other events.
These stars became the nuclear furnaces for heavier elements. The death of these stars spread these metals (in astronomy terms; anything heavier than Helium). This cycle continued until there was enough matter in the protoplanetary disk to form rocky planets, of which we are one (of many).
This article talks about the nuances of how and when carbon became part of this system. While that's certainly interesting, it's the heavier elements (than iron) that I find more interesting. Anyone with rudimentary physics knowledge knows that this path only forms elements up to iron because beyond that it consumes energy.
So heavier elements were seeded in this process through supernovae and, as we've confirmed in recent years, from neutron star mergers. So the right sort of stars need to form in the right way and die and then their remnants need to merge to scatter these elements.
I saw one study that suggested the uranium on earth formed by such an event 80-200 million years before the Earth did. That's kind of crazy to think about.
It is humbling and also rather difficult to get one's head around.
However, when you consider the observable universe is 96bn light-years across and contains hundreds of billions of galaxies, and the observable universe is very likely only a small part of the universe beyond then incredibly unlikely-sounding things will happen all the time somewhere and some when.
It's amazing we know so much considering most of our knowledge about the universe has arisen in the last c.300 years.
(Dinosaurs were around a long time, there were a lot of them, they drank a lot of water which was constantly cycled through the environment. Almost all water got peed by a dinosaur at one point or another.)
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[ 3.1 ms ] story [ 20.1 ms ] threadFirst, the nascent universe had to cool such that nucleons formed, which then became hydrogen. This matter wasn't evenly distributed. Some of it under its own weight collapsed under gravity and birthed the first stars.
It seems that shock waves in nebulae trigger star formation. This could be black holes and/or neutron stars merging, supernovae and possibly other events.
These stars became the nuclear furnaces for heavier elements. The death of these stars spread these metals (in astronomy terms; anything heavier than Helium). This cycle continued until there was enough matter in the protoplanetary disk to form rocky planets, of which we are one (of many).
This article talks about the nuances of how and when carbon became part of this system. While that's certainly interesting, it's the heavier elements (than iron) that I find more interesting. Anyone with rudimentary physics knowledge knows that this path only forms elements up to iron because beyond that it consumes energy.
So heavier elements were seeded in this process through supernovae and, as we've confirmed in recent years, from neutron star mergers. So the right sort of stars need to form in the right way and die and then their remnants need to merge to scatter these elements.
I saw one study that suggested the uranium on earth formed by such an event 80-200 million years before the Earth did. That's kind of crazy to think about.
We are literally made of stardust.
However, when you consider the observable universe is 96bn light-years across and contains hundreds of billions of galaxies, and the observable universe is very likely only a small part of the universe beyond then incredibly unlikely-sounding things will happen all the time somewhere and some when.
It's amazing we know so much considering most of our knowledge about the universe has arisen in the last c.300 years.
Mind-boggling to imagine how all that then led to living objects and finally us exchanging messages on this platform.
Makes you wonder if it all happened by pure chance or if we are all part of an elaborated plan...
https://www.techtimes.com/articles/254435/20201124/water-mad...
(Dinosaurs were around a long time, there were a lot of them, they drank a lot of water which was constantly cycled through the environment. Almost all water got peed by a dinosaur at one point or another.)