When the American Museum of Natural History's Hayden Planetarium stopped calling Pluto a planet, director Neil deGrasse Tyson found himself at the center of a firestorm led by angry Pluto-loving elementary school students. What is it about Pluto—a cold, distant, icy rock—that captures so many hearts? Four years after the IAU (International Astronomical Union) officially reclassified the ninth planet as a plutoid, NOVA travels cross-country with Tyson to find out.

NOVA kicks off the fall season with a return to Ground Zero to witness the final chapter in an epic story of engineering, innovation, and the perseverance of the human spirit. “Ground Zero Supertower” examines the new skyscraper, One World Trade Center, rising up 104 stories and 1,776 feet from the site where the Twin Towers once stood. NOVA also goes underground to see another engineering marvel taking shape here: the construction of the National September 11 Memorial Museum that will house almost a thousand artifacts from that devastating day. In this update of NOVA’s Emmy-nominated special “Engineering Ground Zero,” which featured extraordinary behind-the-scenes access to the struggles of the engineers and architects working at 1 WTC and the 9/11 Memorial, NOVA goes inside the construction of the tower’s final floors and the installation of its soaring, 408-foot spire and beacon.

Machines are everywhere. They run our factory assembly lines and make our coffee. But humanoid robots—machines with human-like capabilities—have long been the stuff of science fiction. Until now. Fueled by an ambitious DARPA challenge, the race is on to design a robot that can replace humans in disaster relief situations. Follow the robots and the engineers that program them as they strive to make their way out of the lab and into the real world. But how capable are they, really? How close are we to a future where humanoid robots are part of our everyday lives? And what will the future look like with robots that can do a human’s job? NOVA investigates the cutting-edge technologies that are advancing robotics—and the enormous challenges that robots still face.