Cosmic Journeys

Saturn's Mysterious Moons

24 min

From the Cassini spacecraft comes one of the greatest photographic collections. Scientists are using it to uncover a trail of clues pointing to the energy sources and complex chemistry needed to spawn life.

The Largest Black Holes in the Universe

24 min

Our Milky Way Galaxy is thought to harbor millions of black holes, the ultra dense remnants of dead stars. But now, in the universe far beyond our galaxy, there's evidence of something far more ominous. A breed of black holes that has reached incomprehensible size and destructive power. Just how large, and violent, and strange can they get?

How Large Is the Universe?

24 min

The mind-blowing answer comes from a theory describing the first micro-moments of our universe. Just as scientists began to make precise measurements of the observable universe, new ideas suggest that our visible patch is an impossibly small portion of the whole.

When Will Time End

24 min

How long will the Universe as we know it survive? The answer depends on whether Stephen Hawking's theory about how black holes decay is right. These strange dense objects are like a clock that tick down to a distant moment when all matter and energy will dissipate into the void.

The Incredible Journey of Apollo 12

24 min

It's the ultimate buddy movie. Pete Conrad and Alan Bean were the second pair of Apollo astronauts to land on the moon. They combined precision with a sense of humor. But it was the rocks they picked up that would define the mission's legacy.

Supermassive Black Hole in the Milky Way Galaxy

24 min

Thick dust and blinding starlight have long obscured our vision into the mysterious inner regions of our Milky Way galaxy. And yet, the clues have been piling up that something important, something strange is going on in there. Astronomers tracking stars in the center of the galaxy have found the best proof to date that black holes exist. Now, they are preparing to capture the first direct image of a supermassive black hole.

Mars: Earth That Never Was

24 min

Did Mars long ago develop far enough for life to arise? If so, does anything still live somewhere underground? The search for answers has revealed the forces that long ago doomed the Red Planet.

The Search for Earth-like Planets

24 min

What is the search for Earth-like planets telling us about our place in the cosmos? Is our Earth one of countless life-bearing worlds strewn about the galaxy, or is it a rare Garden of Eden in a barren universe?

Voyage to Pandora: First Interstellar Space Flight

24 min

Pandora is the idyllic blue world featured in the movie Avatar. Its location is a real place: Alpha Centauri, the nearest star to our Sun and the most likely destination for our first journey beyond the solar system.