Dr. Daniel D'Orazio -- The Black Hole Shuffle

Just how big can black holes get? Well, they can get super-massive! That is, millions to billions of times as massive as the sun. How do we know this? We've detected these supermassive black holes at the centers of galaxies in a number of ways, and Dr. Daniel D'Orazio has been leading the way in figuring out new ways we can detect more, especially if it's not one but two black holes orbiting one another in a binary system.