Before NASA astronauts can fly in new spacecraft from Boeing and SpaceX, they'll have to rack up hundreds of hours of practice on training simulators. This week, two of NASA's commercial crew astronauts tried out new touchscreen simulators in a Boeing facility in St. Louis, preparing to use Boeing's CST-100 Starliner crew capsule and SpaceX's Crew Dragon capsule to dock with the International Space Station.

"These simulators have touchscreen displays, which means they are more versatile than previous spacecraft trainers," said astronaut Suni Williams. "We can run multiple simulations by just changing software and then put that same software into a bigger crew simulator, which we will use to train the whole crew for a spaceflight."

Right now, the astronauts are only running single-person simulations, but later in the year, the simulators will be wired into larger networks to run rehearsals alongside launch and mission controllers. And in early 2017, Boeing will supply a full-sized replica of its Starliner capsule for training.

"The simulations are important for the flight tests, because this is the place to put it all together," said astronaut Eric Boe. "Think of the part-task trainer as our training wheels. As we get more familiar with the systems, the training wheels will come off and we will start advancing to the next systems. Eventually, we will work with another crew member, then with the whole flight control team."