![The United Launch Alliance Atlas V rocket with Boeing's CST-100 Starliner spacecraft atop lifts off from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida on Dec. 20, 2019. Liftoff time was 6:36 a.m. EST.](https://blogs.nasa.gov/commercialcrew/wp-content/uploads/sites/230/2019/12/Boeing-OFT-Launch--1024x576.jpg)
Booster ignition and liftoff of the United Launch Alliance Atlas V rocket at 6:36 a.m. EST from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida. The rocket is on its way, carrying Boeing’s CST-100 Starliner spacecraft on its Orbital Flight Test to the International Space Station. About one minute after launch, the Atlas V rocket will achieve Mach 1. The Atlas V solid rocket boosters will jettison nearly two-and-a-half minutes into the flight.
About two-and-a-half minutes into flight, a series of key events will begin to occur over the next few minutes. The Atlas V solid rocket boosters will fall away shortly after launch. The Atlas first-stage booster engine will cut off, followed by separation from the dual-engine Centaur second stage. The Centaur first main engine will start, following by aeroskirt jettison. A few minutes later the Centaur engine will cut off.