After the first few hundred million years after the big bang pulled matter together to from the first structures in the universe?

Answer 1

After the first few hundred million years following the Big Bang, the universe entered a period known as the "cosmic dawn," during which matter began to coalesce under gravity, forming the first stars and galaxies. This era saw the transition from a hot, dense state to a cooler, more structured universe, leading to the formation of hydrogen and helium clouds. As these structures evolved, they triggered nuclear fusion in stars, creating heavier elements and eventually leading to the complex cosmic structures we observe today. This process laid the foundation for the universe's subsequent evolution and the emergence of galaxies, galaxy clusters, and eventually, planets.