Short answers, pulled from the story.
Emanuel Swedenborg, Immanuel Kant, and Pierre-Simon Laplace developed the nebular hypothesis in the 18th century. This model proposed that the Solar System formed from a collapsing cloud of gas and dust.
The gravitational collapse of a giant molecular cloud began about 4.6 billion years ago. A fragment roughly one parsec across became known as the presolar nebula containing hydrogen, helium, and trace amounts of lithium produced by Big Bang nucleosynthesis.
Jupiter and Saturn entered a 2:1 orbital resonance approximately 4 billion years ago which caused Neptune to surge past Uranus and plow into the ancient Kuiper belt. The Nice model explains how this process shaped the current structure of the outer Solar System.
Evidence for heavy bombardment appears as craters on geologically dead bodies like the Moon and Mercury. The oldest known evidence for life on Earth dates to 3.8 billion years ago following impacts that may have triggered the Late Heavy Bombardment roughly 4 billion years ago.
The Sun will expand to many times its current diameter in approximately five billion years before casting off its outer layers as a planetary nebula. The remnant core will be a white dwarf only the size of Earth but 54 percent of its original mass.