Inner Solar System

Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The formation and evolution of the Solar System is estimated to have begun 4.568 billion years ago with the gravitational collapse of a small part of a giant molecular cloud. Most of the collapsing mass collected in the centre, 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. The Solar System has evolved considerably since its initial formation. Many moons have formed from circling discs of gas and dust around their parent planets, while other moons are thought to have formed independently and later been captured by their planets. Collisions between bodies have occurred continually up to the present day and have been central to the evolution of the Solar System. The positions of the planets often shifted, and planets have switched places. This planetary migration now is thought to have been responsible for much of the Solar System's early evolution. Learn more about Solar System, our corner of the universe, its formation and evolution in the following pages.