NPR's Ari Shapiro speaks with Regina Barber and Aaron Scott of Short Wave about a black hole nearly as old as the universe, how pollution plagues sea turtles, and a simple fix to cut blood pressure.

Green sea turtles are among the largest marine turtles, with adults growing up to 4 feet long (1.22 meters) and weighing an average of 350 pounds (158.8 kilograms).