Formation of the Solar SystemFormation of the Solar System

Our solar system was born from the collapse of a great cloud of gas. A nebula that formed from hydrogen gas and the remnants of supernovae.

•The gravitational collapse of a great cloud of interstellar gas causes increased Pressure and Temperature.

•Density increases and collisions increase.

•The conservation of angular momentum leads to increased rotation as the size of the cloud gets smaller.

•Due to collisions and gravitational forces, the spinning disk flattens out as it spins.

•The highest density is in the center of this spinning disk, where gas collapses far enough that it can ignite nuclear fusion and a star is born.

Conservation of Angular MomentumConservation of Angular Momentum

•Individual stars can form in smaller sections of larger clouds of gas. In a large nebula, many stars may be born.

•As stars are born, solar wind and pressure can lead to further birth of stars.

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Disks around Other StarsDisks around Other Stars

Observations of disks around other stars support the Observations of disks around other stars support the nebular hypothesis.nebular hypothesis.

Temperature and density differences tend to cause different types of planets to form.

Those that are in the hotter center area may form rocky planets, while those farther out, beyond the “frost line” tend to be cooler planets of condensed gas. These are the large gas giants.

Debris is pulled toward the hot center of the gas cloud. It collides and accretes into planetesimals and gradually terrestrial sized planets.

Eventually, the star ignites and solar wind clears out the remaining gas from the inner solar system.

Heavy bombardment leads to pock-marked worlds. This heavy bombardments causes worlds, like the primitive Earth to grow and heat. Asteroids and comets bring metals and water and other compounds to the primitive worlds.

Water would have come to Earth from planetesimals farther out in the solar system.

It is possible that the Earth-Moon system was formed from the violent collision of the early Earth with a Mars-sized planet.

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Giant ImpactGiant Impact

In Summary:

1. A huge cloud of gas condenses and spins, flattening out into a disk.

2. The core heats up and inside a “frost line” terrestrial planets form. Outside of this, gas giants form.

3. The Solar System undergoes millions of years of collisions, and planets grow.

4. Over time, the gravitational influences stabilize the solar system.

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The Formation of the Moon