19K views · 1.7K reactions | When the Earth first formed from clouds of dust and gas 4.5 billion years ago , it was – like so many other lifeless worlds in the universe – devoid of an atmosphere , an inhospitable rock floating in the black void of space . But as the young planet was pummelled by asteroids , a period of extraordinary upheaval began . . . Get the accompanying book to the #Earth series at chrispackh.am/earth-book | Chris Packham | Facebook