Live Updates: NASA and SpaceX to launch astronauts to the ISS

Joe Raedle/Getty Images

Joe Raedle/Getty ImagesBy CATHERINE THORBECKE, ABC News

(MERRITT ISLAND, Fla.) -- History is being made Wednesday as NASA and SpaceX gear up to launch Americans into space from American soil and on American equipment for the first time in nearly a decade.

The SpaceX Demo-2 launch is scheduled to liftoff at 4:33 p.m. ET from the Kennedy Space Center in Florida. The Crew Dragon spacecraft, propelled by a Falcon 9 rocket, will carry NASA astronauts Robert Behnken and Douglas Hurley to the International Space Station.

The launch is historic in part because it ends a nearly 10-yearlong U.S. dependency on Russia for seats to space. It also marks the first time Elon Musk's private space firm, SpaceX, is launching astronauts.

"It reestablishes an essential capability if the United States is really going to be the leading space-faring country in the world, it needs the ability to launch its own people with its own equipment from its own territory," John Logsdon, a professor emeritus at George Washington University's Space Policy Institute and former member of the NASA Advisory Council, told ABC News ahead of the launch. "It removes an almost embarrassing dependence that has persisted for the last nine years."

Here is the latest on the milestone launch for the U.S. space program:

Weather forecast for launch includes chance of showers, possible thunderstorms

The weather forecast ahead of the launch in Cape Canaveral, Florida, includes a chance of some showers, possible thunderstorms, and potentially, some electrically charged clouds.

Major weather concerns ahead of the launch are rain and lightning. Residual electrical charges from leftover thunderstorms might interact with the rocket which has a charge itself as it goes through the troposphere and can cause trigger lightning, according to ABC News' chief meteorologist Ginger Zee.

As of Wednesday morning, the launch mission's executive forecast predicted a 50% probability of violating weather constraints.

Copyright © 2020, ABC Audio. All rights reserved.