With repeated triumphs and new challenges comes increasing risk, until loss breaks the pattern. The white-knuckle suspense thriller of Apollo 13's famous near-disaster is only a triumphant prelude to darker moments ahead. The launch of the space shuttle program promises routine trips to Earth orbit for many new astronauts. But just when that promise seems fulfilled, routine shuttle launches begin to bore the public. NASA responds by training a school-teacher to fly, in order to teach children lessons from space. Christa McAuliffe's life is tragically cut short as she and the rest of the crew perish aboard the shuttle Challenger. All missions are halted. Eventually the shuttle returns to orbit, for fifteen years of successful missions until disaster strikes again with the shocking loss of Columbia. It would be the beginning of the end for the shuttle.
We’ve covered a lot of incredible stuff, but this week we’re talking about the weirdest objects in space: BLACK HOLES. Stellar mass black holes form when a very massive star dies, and its core collapses. The core has to be more than about 2.8 times the Sun’s mass to form a black hole. Black holes come in different sizes, but for all of them, the escape velocity is greater than the speed of light, so nothing can escape, not matter or light. They don’t wander the Universe gobbling everything down around them; their gravity is only really intense very close to them. Tides near a stellar mass black hole will spaghettify you, and time slows down when you get near a black hole — not that this helps much if you’re falling in.
Now that gravitational waves are definitely a thing, it’s time to think about some of the crazy things we can figure out with them. In some cases we’re going to need a gravitational wave observatory - in fact, we've already built one.