Putting the history of Earth into perspective

The Earth is really, really old. Over 4 1/2 billion years old, in fact. How do we begin to comprehend a number that large? It helps to put it on a more fathomable scale. Watch to see where Earth's major events would fall on a timeline stretching across the US. Subscribe to BI: Science - ----------------------------------------­---------- Follow BI Video on Twitter: Follow BI Video On Facebook: Read more