Uranus and Neptune, two of the largest, farthest and strangest planets in our solar system. These two planets break all the rules. Of all the big planets, Uranus and Neptune remain the biggest enigmas. Today, astronomers are finally unlocking why these supersized snowballs are so weird. Can an ancient mega-collision reveal what knocked Uranus onto its side? Can a missing twin world unlock why one of Neptune's moons orbits the wrong way? And what is the energy that drives the fastest winds in the solar system?

Supermassive black holes are the engines that power our universe and one of the major players in the evolution of galaxies. They're in fact the driving force at the heart of nearly every galaxy in the cosmos. Now, a new mystery has emerged about the oldest supermassive black holes. We see supermassive black holes in the very early universe. And we don't understand how they grew so large so quickly. We have clues about their formation but, can we solve the mystery of this supermassive growth spurt?

There's a killer lurking in our galaxy, a star ready to explode into a supernova. Seen from Earth, a supernova in the Milky Wave would have a terrible beauty. But for us, it could be fatal. In a few seconds, it can release as much energy as the sun will over its entire lifetime. It could be anywhere. It is nearly impossible to predict where and when the next supernova will happen. The hunt is on to find the next supernova before it finds us.

This is the story of two of the biggest scientific breakthroughs of the 21st century, told by the incredible scientists who made them happen. The first is LIGO’s measurement of gravitational waves coming from a black hole merger, and the second, the Event Horizon Telescope’s image of a black hole.

NASA's revolutionary Juno Probe had a goal visiting Jupiter -- to reveal the deepest mysteries of the Solar System. Everything we see in the our planetary system today is affected by Jupiter somehow in the past or now. So in many ways, Juno is actually giving us a view into the history of the Solar System.
But there are many other questions. Does Jupiter have a core? Why it has a surprisingly warm atmosphere? What's driving Jupiter's storms? What is going on its weird cyclones, its gigantic swirls? The auroras of Jupiter are tremendously large, bigger than the planet itself. where are they coming from? What we're learning, what we're unlocking, it's mind-blowing.

In just one generation, our ability to search for planets beyond our solar system has transformed. With modern techniques and telescopes, planetary scientists have found thousands of exoplanets in our universe, and many of them have the perfect conditions for life. Are we about to find Earth’s twin?