An artist's depiction of Planet Nine. The object is thought to be gaseous, similar to Uranus and Neptune. Hypothetical lightning lights up the night side.
Joe Palca is a science correspondent for NPR. Since joining NPR in 1992, Palca has covered a range of science topics — everything from biomedical research to astronomy. He is currently focused on the eponymous series, "Joe's Big Idea." Stories in the series explore the minds and motivations of scientists and inventors. Palca is also the founder of NPR Scicommers – A science communication collective.
Critics say diplomacy with Iran may have been a cover for military buildup, as questions grow over whether the U.S. walked away from a real chance at a deal.
Thousands die every year waiting for an organ donation. The Indicator team talks to two economists who argue that paying the families of organ donors would save lives.
In the new HBO special from Chris Fleming, the comedian spends a lot of time talking about Terry Gross. Wild Card host Rachel Martin talks to Fleming about what he loves about the Fresh Air host.