The Universe: Earth's Celestial Neighbors and Cosmic Enemies *3 Hour Marathon*

Asteroids and comets may be responsible for the delivery of a lot of the building blocks of life. See more in this three hour marathon from The Universe. #TheUniverse Subscribe for more from The Universe and other great The HISTORY Channel shows: http://histv.co/SubscribeHistoryYT Find out more about the show and watch full episodes on our site: http://www.history.com/shows/ Check out exclusive The HISTORY Channel content: History Newsletter - https://histv.co/newsletter Website - https://histv.co/History Facebook - https://histv.co/Facebook Twitter - https://histv.co/Twitter HISTORY® is the leading destination for award-winning original series and specials that connect viewers with history in an informative, immersive, and entertaining manner across all platforms. The network’s all-original programming slate features a roster of hit series, premium documentaries, and scripted event programming.