It is some men's great dream to explore the world. Today we present Solar Impulse 2, an aircraft, powered only by the sun that will attempt the first solar flight around the world. What is Solar Impulse? The only airplane of perpetual endurance, able to fly day and night on solar power, without a drop of fuel. Get more information here about the project.

Why would a killer whale go after a great white shark? Enter Alisa Schulman-Janiger, a biologist who is very familiar with the different families of killer whales off the coast of California.

In this first of two segments, learn valuable information regarding bottled water: its origin, its marketing to the masses and its effect upon our environment.

The solar airplane Solar Impulse 2 was presented on April 9th, 2014. The construction of the experimental solar aircraft didn't happen in a day. Watch this video about the construction of Solar Impulse 2 and understand the steps that had to be taken to attempt the first solar flight around the world!

David and Ben Crystal explain what goes into original pronunciation (OP) productions of Shakespeare and what they reveal about the history of the English language.

Occupy Wall Street is an ongoing movement based in the heart of New York City’s Wall Street financial district. Demonstrators are protesting against social and economic inequality, corporate greed and corruption.

In this second of two segments, learn about the alternatives to bottled water and what you can do to help protect our environment.

At times, Doc Gruber's research requires the team to dive right into shark-infested waters! Their line of work certainly isn't for the faint of heart! Enjoy.

All Hands Volunteers is a US-based, non-profit organization that provides hands-on assistance to survivors of natural disasters around the world with maximum impact and minimum bureaucracy. Their mission is to enable volunteers to provide assistance to communities affected by natural disasters.

Nathalie and Jim get up close and personal with tiger and lemon sharks, trying to get the best footage while taking care not to disturb or excite the dangerous animals.

WWF marine advocate Bob Zuur out at night on penguin patrol as part of the Oiled Wildlife Response team.

The world’s worst human rights abuses require permanent solutions. The Enough Project uses cutting-edge research, advocacy and campaigning to work toward ending genocide and crimes against humanity.

In a recent trip across the Sudanese border into rebel-held territory in Sudan’s Nuba Mountains, George Clooney witnessed rocket attacks and the effects of aerial bombardment by the Sudanese regime against the Nuban people. This trip diary was written and directed by George Clooney in the field with the Enough Project.

In this episode, Doc Gruber and a colleague are testing a shark repellent. If effective, it could help save the lives of divers, swimmers and surfers all over the world.

Rosetta revisits the exciting scientific discoveries she has made during her time at Comet 67P/Churyumov-Gerasimenko, including the successful search to find Philae. Now it's time to start preparing to descend to the comet for the end of her extraordinary mission.