Suni Williams practices docking operations

Commercial Crew astronaut Suni Williams practices docking operations for Boeing's CST-100 Starliner using a simulator designed to mimic the controls and behavior of the spacecraft. The Starliner is one of two spacecraft in development in partnership with NASA's Commercial Crew Program that will enable astronauts to fly to the International Space Station on a new generation of spacecraft made in America and launching from Florida's Space Coast. Working at Boeing's St. Louis facility, Williams and astronaut Eric Boe ran through numerous mission phases to assess the machines – called part-task trainers – before they are shipped to NASA's Johnson Space Center in Houston later this year. Photo credit: NASA/Dimitri Gerondidakis