A habitable planet
Life has existed on Earth for billions of years. Stabilising mechanisms have helped our planet remain habitable to this day. It all began 4.5 billion years ago, when the debris from previous generations of stars formed a large molecular cloud. A part of this collapsed under its own gravity to create a new star - our Sun. The remaining gas and dust flattened into a spinning disc around this newly formed star. Over time, small particles of dust clumped together into kilometre-sized bodies called planetesimals, which eventually accreted into Earth and the other rocky planets. A final catastrophic collision between our newly formed planet and another large object ejected debris into Earth's orbit, which gradually coalesced to form the Moon.
