On March 9, 2015, Solar Impulse II took off from Abu Dhabi on one of the greatest aviation adventures of our time: the first solar-powered flight around the world. Together with a team of brilliant engineers, two visionary pilots—Bertrand Piccard and André Borschberg—designed and built Solar Impulse from scratch, even though top airplane manufacturers told them it would be “impossible to control.”

Pilot André Borschberg describes how it feels to fly in a plane entirely powered by the sun.

One unlucky day 13,000 years ago, a slight, malnourished teenager missed her footing and tumbled to the bottom of a 100-foot pit deep inside a cave in Mexico’s Yucatán. Rising seas flooded the cave and cut it off from the outside world—until a team of divers chanced upon her nearly complete skeleton in 2007.

Pilot André Borschberg reflects on his experience achieving what seemed impossible.

Take a look back with us at the biggest science stories of 2017.

In honor of the New Year, we bring you a NOVA retrospective on ballistics.

Could a safety technology have prevented a train crash in Washington that killed three?

Crows can remember the face of their captors—even after generations.

Watch astonishing tests of avian aptitude: parrots that can plan for the future, jackdaws that can “read” human faces, and crows that can solve multi-step puzzles with tools like pebbles, sticks, and hooks. Could these just be clever tricks, based on instinct or triggered by subtle cues from their human handlers?

Here are three mind-blowing ideas for what may be inside a black hole.

As a child, theoretical astrophysicist Priya Natarajan loved atlas. As an adult, she maps the cosmos.

As a kid, Janna Levin loved cosmology—now, she’s an award-winning author and host of “Black Hole Apocalypse”

Chung-Pei Ma is both a gifted violinist and one of the world’s foremost black hole hunters.

NOVA has teamed up with Cook's Illustrated to cook up a recipe for stars and black holes.

Andrea Ghez asks the ultimate question: Is there a supermassive black hole at the center of our galaxy?

Black holes are the most enigmatic and exotic objects in the universe. They’re also the most powerful, with gravity so strong it can actually trap light. And they’re destructive. Anything that falls into them vanishes…gone forever. But now, astrophysicists are realizing that black holes may be essential to understanding how our universe unfolded—possibly leading to life on Earth and us.

Black holes are the most enigmatic and exotic objects in the universe. They’re also the most powerful, with gravity so strong it can actually trap light. And they’re destructive. Anything that falls into them vanishes…gone forever. But now, astrophysicists are realizing that black holes may be essential to understanding how our universe unfolded—possibly leading to life on Earth and us.

Black holes are mind-blowing. Discover the FOUR types of black holes that exist in the cosmos.

66 million years ago, a seven-mile-wide asteroid collided with Earth, triggering a chain of events that coincide with the end of the dinosaurs. But experts have long debated exactly what happened when the asteroid struck and how the giant beasts met their end. Now, scientists have uncovered compelling new clues about the catastrophe.

Anywhere information goes, even in your mind, energy goes with it—bottle up that energy and it has mass.