Boeing's big launch Friday will put its Starliner to the test

Why it matters: NASA has relied on Russia's Soyuz spacecraft and rocket to bring its astronauts to the space station and back to Earth since the end of the space shuttle program.

• With Starliner and SpaceX's Crew Dragon, the space agency hopes to end that dependency in favor of launching people from the U.S. again.
• If this uncrewed test goes well, it could pave the way for Boeing to launch its first crewed mission to the station in early 2020.

Details: Starliner is expected to take flight at 6:36am ET Friday atop an Atlas V rocket from Cape Canaveral, Florida.

• The spacecraft comes equipped with life support systems that will be needed for its first crewed mission and an anthropomorphic test dummy named Rosie.
• Rosie — named after Rosie the Riveter — is outfitted with a host of sensors to keep an eye on what an astronaut might experience during flight.
• The capsule will also deliver supplies to the astronauts, including a clutch of holiday presents, when it docks to the station about 24 or 25 hours after launch.

What to watch: It will be interesting to see which company — Boeing or SpaceX — manages to launch its first crews to space.

• The two companies have faced major delays with budget shortfalls and technical issues setting them back, but now, both seem to be on the verge of flying their first NASA astronauts to orbit.
• SpaceX — which has already done its uncrewed test flight to the station — is expected to prove out the Crew Dragon's abort system during an in-flight test in January.

Go deeper: SpaceX and Boeing inch toward sending people to space