In her brutally honest, ironically funny and widely read meditation on death, "You May Want to Marry My Husband," the late author and filmmaker Amy Krouse Rosenthal gave her husband Jason very public permission to move on and find happiness. A year after her death, Jason offers candid insights on the often excruciating process of moving through and with loss -- as well as some quiet wisdom for anyone else experiencing life-changing grief.

What if we could save the fishing industry and protect the ocean at the same time? Marine ecologist Enric Sala shares his bold plan to safeguard the high seas -- some of the last wild places on earth, which fall outside the jurisdiction of any single country -- by creating a giant marine reserve that covers two-thirds of the world's ocean. By protecting the high seas, Sala believes we will restore the ecological, economic and social benefits of the ocean. "When we can align economic needs with conservation, miracles can happen," Sala says.

What if we could use the cold darkness of outer space to cool buildings on earth? In this mind-blowing talk, physicist Aaswath Raman details the technology he's developing to harness "night-sky cooling" -- a natural phenomenon where infrared light escapes earth and heads to space, carrying heat along with it -- which could dramatically reduce the energy used by our cooling systems (and the pollution they cause). Learn more about how this approach could lead us towards a future where we intelligently tap into the energy of the universe.

Can a bird that symbolizes death help the living catch criminals? In this informative and accessible talk, forensic anthropologist Lauren Pharr shows us how vultures impact crime scenes -- and the assistance they can provide to detectives investigating murders. (This talk contains graphic images.)

Can a bird that symbolizes death help the living catch criminals? In this informative and accessible talk, forensic anthropologist Lauren Pharr shows us how vultures impact crime scenes -- and the assistance they can provide to detectives investigating murders. (This talk contains graphic images.)

Can a bird that symbolizes death help the living catch criminals? In this informative and accessible talk, forensic anthropologist Lauren Pharr shows us how vultures impact crime scenes -- and the assistance they can provide to detectives investigating murders. (This talk contains graphic images.)

Research investigator Michael Hendryx studies mountaintop removal, an explosive type of surface coal mining used in Appalachia that comes with unexpected health hazards. In this data-packed talk, Hendryx presents his research and tells the story of the pushback he's received from the coal industry, advocating for the ethical obligation scientists have to speak the truth.

"You do not mess with something so fundamental, so precious, as science," says Kirsty Duncan, Canada's first Minister of Science. In a heartfelt, inspiring talk about pushing boundaries, she makes the case that researchers must be free to present uncomfortable truths and challenge the thinking of the day -- and that we all have a duty to speak up when we see science being stifled or suppressed.

"You do not mess with something so fundamental, so precious, as science," says Kirsty Duncan, Canada's first Minister of Science. In a heartfelt, inspiring talk about pushing boundaries, she makes the case that researchers must be free to present uncomfortable truths and challenge the thinking of the day -- and that we all have a duty to speak up when we see science being stifled or suppressed.

Local humanitarians are beacons of light in the darkness of war, says humanitarian aid entrepreneur and TED Fellow Rola Hallam. She's working to help responders on the ground in devastated communities like Syria, where the destruction of health care is being used as a weapon of war. One of her campaigns achieved a global first: a crowdfunded hospital. Since it opened in 2017, the aptly named Hope Hospital has treated thousands of children. "Local humanitarians have the courage to persist, to dust themselves off from the wreckage and to start again, risking their lives to save others," Hallam says. "We can match their courage by not looking away or turning our backs."