Nebula Collapse and Birth
The solar system's formation started with a nebula's collapse, possibly triggered by a supernova's shockwave. The gravity-driven implosion caused the nebula to spin, forming a flattened, rotating disk.
Protoplanetary Disk Emergence
Within this spinning disk, called the protoplanetary disk, temperature variations caused different materials to segregate, with heavier elements near the center and lighter ones farther out.
First Generation Planets?
The solar system may have had an initial generation of planets that were devoured or ejected by the sun before the current planets formed, reshaping early solar system architecture.
Planetesimals and Accretion
Dust and rock within the disk collided and stuck together, forming planetesimals. These building blocks then gradually accreted to form the planets, a process taking tens of millions of years.
Giant Planets' Grand Tack
Jupiter may have migrated towards the sun, then reversed after Saturn's formation, a journey termed 'The Grand Tack,' profoundly influencing the inner solar system's structure and asteroid belt.
Late Heavy Bombardment
Approximately 600 million years after formation, the solar system experienced a spike in impacts known as the Late Heavy Bombardment, possibly caused by planetary migration destabilizing asteroid and comet orbits.
Organic Compounds' Mystery
Organic compounds found on asteroids and comets suggest complex chemistry occurred in the protoplanetary disk, hinting at prebiotic materials' presence before Earth's formation, which raises intriguing possibilities for life's origins.