NOVA celebrates the 400th anniversary of the telescope with Hunting the Edge of Space, a two-part special which reveals the technological innovations and scientific discoveries that have marked the history of this hugely important invention.

After centuries of engineering, the telescope has come a long way from Galileo's simple spyglass. Perched on mountaintops, orbiting the earth and even circling other planets, these modern machines are uncovering secrets of the universe that 17th-century astronomers could only dream of. Viewers are introduced to today's most powerful telescopes and the scientists who are using them to answer some of our biggest questions about the cosmos.

The film features Nobel Prize winner Arno Penzias, who, with Robert Wilson, discovered proof of the big bang with one of the first radio telescopes, and Alex Filippenko, a member of the team of astronomers who used the giant Keck telescope in Hawaii to capture distant supernovae and unveil the existence of dark energy.