NOVA Season 53 — episode guide & air dates

Imagine a time when Earth was a molten, volcanic wasteland, heavily bombarded by colossal asteroids. We’ve long feared these cosmic impacts as destroyers of life, but what if they were the key to our very existence? Explore a revolutionary theory suggesting that these violent collisions provided the essential ingredients – water, minerals, and energy – needed for life to ignite on our planet. Discover how scientists are unearthing evidence from lunar rocks and ancient impact craters, revealing that the very objects known for extinguishing life might have actually sparked it.

Uncover the lost secrets of a once-mighty empire. The city of Angkor, the seat of the great Khmer Empire in Southeast Asia for 500 years, was once the biggest city in the world. For centuries, this incredible civilization flourished, building the largest religious monument on Earth, Angkor Wat, and mastering urban engineering in a challenging landscape. But then it was mysteriously abandoned, swallowed by the jungle. Now, cutting-edge technology and new discoveries are finally revealing how this astounding empire rose to global prominence – and what likely led to its devastating collapse. Follow a scientific detective story that is challenging everything we thought we knew about this ancient metropolis.

Imagine a world where your furry best friend could tell you exactly what they're thinking. A growing number of dog owners claim this is already happening, thanks to innovative word buttons that seem to unlock a new realm of canine communication. But are these dogs truly understanding what we’re saying — and talking back? Are they really thinking creatively, applying words in new contexts? Or is this just clever conditioning? To find out, scientists are conducting the largest animal communication study in history, analyzing millions of button presses from thousands of dogs worldwide. Witness astonishing moments that challenge our assumptions about animal intelligence, from dogs that seemingly engage in conversations to those who learn new words with incredible speed. Prepare to question everything you thought you knew about the minds of dogs and discover just how far their linguistic abilities might stretch.

Uncover the surprising ancient origins of mammals, a story that began long before the dinosaurs' reign. Surveying Earth's tumultuous past reveals how some of our earliest ancestors, the therapsids – creatures that looked like reptiles but were starting to develop mammalian traits – survived multiple global catastrophes. Through remarkable adaptations like burrowing and the emergence of warm-bloodedness, they forged a lineage that persevered against all odds. Fascinating fossil clues and cutting-edge science reveal how a small, resilient group of animals faced extinction events, outlived giants, and ultimately gave rise to the diverse world of mammals we know today, including us.

On a remote hillside in modern-day Turkey sits Gpbekli Tepe, the oldest temple on Earth. For centuries, archaeologists believed it was a religious center built by nomadic hunter-gatherers before the rise of civilization. But groundbreaking new evidence reveals that a sophisticated community of settled hunter-gatherers, not nomads, lived here year-round for centuries. This startling discovery could be the missing link in humanity's momentous transition from hunting to farming. Follow experts as they use new digs and shattered skulls to piece together a captivating story that could forever change our understanding of the roots of civilization.