Solar System
OverviewDefinitionFormation and evolutionGeneral characteristicsSunInner Solar SystemOuter Solar SystemTrans-Neptunian region
The Solar System is the gravitationally bound system of the Sun and the masses that orbit it, most prominently its eight planets, of which Earth is one. The system formed about 4.6 billion years ago when a dense region of a molecular cloud collapsed, creating the Sun and a protoplanetary disc from which the orbiting bodies assembled. Inside the Sun''s core hydrogen is fused into helium for billions of years, releasing energy which is over even longer periods of time emitted through the












