The air war in Afghanistan showed that sometimes the hottest pilots are sitting on the ground operating the remote controls of UAVs—or unmanned aerial vehicles. In newly declassified footage, "Spies That Fly" reveals the astounding capabilities of UAVs and the ambitious plans for future models.

In "Origins: Where are the Aliens?," host astrophysicist Neil deGrasse Tyson explores such provocative questions as: would "ETs" resemble us or the creatures of science fiction? Are there "aliens" already amongst us on Planet Earth—brainy creatures whose intelligence is very different from our own? And are planets on which life can flourish rare or common in our universe?

Can lessons learned from the Twin Towers' collapse make new buildings safer?

As the Earth heats up at a dangerous rate and fossil fuels become scarcer, ordinary citizens and businesses are bypassing the federal government to lead the way in exploring a clean, renewable source of power: the sun. In this report, NOVA shines a light on how and why people across America and the world are "going solar," using radiant energy of the sun to power homes, businesses, and even entire communities. But can everyday people really make a difference by using solar power? And can solar technologies, with their high cost and logistical challenges, truly play a bigger role in powering the future of humanity? The grand hopes, latest innovations, roiling controversies, and practical realities of solar power all come to the fore in this program.

As Governor of California, Arnold Schwarzenegger launches a dramatic and controversial program to slash carbon dioxide emissions and promote energy efficiency. NOVA explores the pros and cons of California's bold approach, which calls for improvements in energy efficiency in homes and commercial buildings; increased reliance on renewable power sources, primarily solar and wind; and major upgrades in car mileage. Hear from Governor Schwarzenegger, skeptics and supporters of the plan, and ordinary citizens and businesspeople whose lives are impacted. Among those interviewed is Steven Chu, who went on to become the U.S. Energy Secretary in the Obama Administration.