Scientists continue to learn more about black holes in space, places where the pull of gravity is so strong that not even light can escape. Black holes occur after supergiant stars explode into brilliant but short-lived supernovas. All the matter dispersed by that titanic explosion collapses in a few weeks or months, and gravity crushes it all into a tiny space. Now data from a Japanese satellite is helping decipher the secrets of these invisible singularities. VOA's Deborah Block has more.