A neuroscientist and engineer, Daniel Wolpert studies how the brain controls the body.

Tweeting (and covering Bowie) from the International Space Station last year, Colonel Chris Hadfield reminded the world how much we love space.

As the cofounder and executive director of Waterford UPSTART, Claudia Miner has one goal: to help families overcome barriers and prepare their children for lifelong learning.

James Rhee is an acclaimed entrepreneur, leader and goodwill strategist

Oxford professor Richard Dawkins has helped steer evolutionary science into the 21st century, and his concept of the "meme" contextualized the spread of ideas in the information age. In recent years, his devastating critique of religion has made him a leading figure in the New Atheism.

Jonathan Klein runs Getty Images, a stock photo agency whose vast archive of still photography and illustrations is a mainstay of the creative class.

Mariana Mazzucato helps policymakers understand how the global economy really works (and how we need to fix it).

Rahwa Ghirmatzion is executive director of People United for Sustainable Housing, a membership-based community organization committed to social and climate justice.

Lisa Godwin is an educator with the Onslow County School District of North Carolina.

A political strategist focused on creating a better future, Tom Rivett-Carnac works at the highest levels of business and government to find creative ways to accelerate solutions to the climate crisis.

Dr. George Blair-West is an author, researcher and doctor specializing in psychiatry.

Robin Steinberg is the CEO of The Bail Project, an organization designed to combat mass incarceration in the United States by disrupting the money bail system -- one person at a time. As she says: "I hate injustice and simply can't sit still when I see it."

Kathy Nicholson Hull founded the first freestanding pediatric palliative care center in the US.

Vera Songwe is the UN Under-Secretary General and the executive secretary of the Economic Commission for Africa.

The director of the award-winning documentary The War Tapes, Deborah Scranton is committed to using new technology to give people power to tell their own stories.

Maajid Nawaz works to promote conversation, tolerance and democracy in Muslim and non-Muslim communities.

The founder of the Tinkering School, Gever Tulley likes to build things with kids.

Sergei Lupashin imagines new uses for flying robots. He's a 2014 TED Fellow.

James Beacham is an experimental high-energy particle physicist working with the ATLAS collaboration at CERN's Large Hadron Collider.

Drawing on a rich cultural and personal history, Olúfẹ́mi Táíwò studies philosophy of law, social and political philosophy, Marxism, and African and Africana philosophy.

Socio-ecological artist

Farmer + technologist

Entrepreneur and Bassist

Artist Researcher, Aquabatics

African tech entrepreneur

Environmentalist

Entrepreneur + educator