<P> The formation and evolution of the Solar System began 4.6 billion years ago with the gravitational collapse of a small part of a giant molecular cloud . Most of the collapsing mass collected in the center , forming the Sun , while the rest flattened into a protoplanetary disk out of which the planets , moons , asteroids , and other small Solar System bodies formed . </P>
<P> The formation and evolution of the Solar System began 4.6 billion years ago with the gravitational collapse of a small part of a giant molecular cloud . Most of the collapsing mass collected in the center , forming the Sun , while the rest flattened into a protoplanetary disk out of which the planets , moons , asteroids , and other small Solar System bodies formed . </P>
when did our solar system begin to form
when did our solar system begin to form
4.6 billion years ago
4.6 billion years ago