Secrets of the Space Probes

S5, E5: They've discovered water on other planets, and snatched the actual building blocks of life from a comet's tail. But can space probes find a new Earth...and even make contact with alien life? In the 21st century, space probes are photographing, drilling and even sniffing new worlds in the quest for life, and scanning thousands of distant suns trying to detect Earth-like planets. It's only a matter of time before space probes unlock the secrets to extra-terrestrial life and the universe itself.