The WORST seasons of When We Left Earth: The NASA Missions

Every season of When We Left Earth: The NASA Missions ever, ranked from worst to best by thousands of votes from fans of the show. The worst seasons of When We Left Earth: The NASA Missions!

NASA unlocks their vaults and lends their footage to the Discovery Channel to form this fascinating HD series. Narrated by Gary Sinise, this collection of training videos, home movies and more detail some of the first missions to the moon.