Threshold 2: Stars Light Up발음듣기
Threshold 2: Stars Light Up
Threshold 2: Stars Light Up
(light music) Right off to the big bang our young universe was what scientist called a plasma.
This was basically an incredibly hot mush of charged particles with that much structural or complexity.
About 380,000 years later things began to change.
By then, temperatures had fallen low enough for protons, which are positive charges, to link up with electrons, which are negative charges, and together they formed electrically neutral atoms.
Pretty simple ones like hydrogen, some helium, and a few slightly heavier atoms thrown in for good measure.
The universe now contained fast clouds of these atoms and gravity and now you have the ingredients for our second threshold.
The formation of stars. Here's what happened next.
Wherever there was slightly more matter, gravity is more powerful.
Tiny variations in the density of matter became the first Goldilocks condition for this second threshold.
Gravity packed slightly against the regions and a little closer together squashing them so tightly that they began to heat up.
This growing pressure in heat created our second Goldilocks condition.
Eventually, the clouds got so hot the protons and electrons split apart once more recreating a plasma.
When temperatures in these hot spots got to about 10 million degrees Celsius, protons began to fuse together.
Part of them turned into energy, as they did so.
This huge release of heat, from the center of each cloud of matter, stopped the cloud from collapsing any further.
This is how the first stars lit up.
Soon, the universe had billions of hot spots pouring energy into the cold of deep space.
Each star would continue to release energy into space for millions or even billion of years until it had no more protons to fuse.
As these stars formed, so did galaxies, each containing billions of stars.
Galaxies in term group together into huge clusters and chains of galaxies.
The largest structures in the universe.
Suddenly, the universe seemed to have a lot more variety and a lot more structure.
What new things could happen in a universe filled with stars? (light music)
(light music) Right off to the big bang our young universe was what scientist called a plasma.발음듣기
This was basically an incredibly hot mush of charged particles with that much structural or complexity.발음듣기
By then, temperatures had fallen low enough for protons, which are positive charges, to link up with electrons, which are negative charges, and together they formed electrically neutral atoms.발음듣기
Pretty simple ones like hydrogen, some helium, and a few slightly heavier atoms thrown in for good measure.발음듣기
The universe now contained fast clouds of these atoms and gravity and now you have the ingredients for our second threshold.발음듣기
Tiny variations in the density of matter became the first Goldilocks condition for this second threshold.발음듣기
Gravity packed slightly against the regions and a little closer together squashing them so tightly that they began to heat up.발음듣기
Eventually, the clouds got so hot the protons and electrons split apart once more recreating a plasma.발음듣기
When temperatures in these hot spots got to about 10 million degrees Celsius, protons began to fuse together.발음듣기
This huge release of heat, from the center of each cloud of matter, stopped the cloud from collapsing any further.발음듣기
Each star would continue to release energy into space for millions or even billion of years until it had no more protons to fuse.발음듣기
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