Boeing's uncrewed Starliner spacecraft landed at White Sands Space Harbor in New Mexico on Wednesday at 6:49 p.m. EDT, ending a six-day-long mission to the International Space Station.

Starliner undocked from ISS at 2:36 p.m. EDT to start its journey back to Earth, with it's parachute-assisted touchdown expected about four hours later at 6:49 p.m. EDT at White Sands Space Harbor at the U.S. Army's White Sands Missile Range in New Mexico.

"It's awesome to see the Starliner materialize in the sky, under its parachutes, and then successfully landing," Dan Huot a NASA public affairs officer, said during the agency's livestream of the landing.

"It's a great day for NASA and a great day for Boeing," Huot said.

Teams from NASA and Boeing will now safe the vehicle, which involves collecting the heat shield that was jettisoned on the way down, as well as preparing an environmental enclosure as they get Starliner ready for eventual transport back to Boeing's facilities.

The landing marked the end of Starliner's first trip to the orbital outpost, which is one of the final major milestones the craft had to complete before it is certified to fly astronauts.

"Starliner has performed beautifully, completing many of its flight test objectives while on orbit, including establishing a joint ventilation system with the ISS and recharging its batteries with space station power," Mark Nappi, Starliner program manager at Boeing, told UPI in an interview ahead of its departure from ISS.

Just after 3 p.m. EDT, the craft fired the first of its planned burns to help maneuver away from the station, with departure burns next to come.

Operation Flight Test-2 was Starliner's chance to prove it can launch and dock itself to the orbital outpost -- and a second attempt at the test, following one in 2019 -- ahead of expectations it will take its first crew to ISS later this year.

As part of the mission, engineers tested the craft's onboard systems, including it's autonomous flight system, which approached, backed away from and then docked with the ISS.

NASA astronauts Kjell Lindgren and Bob Hines also tested the craft's communications system with the ISS, in addition to unloading more than 500 pounds of supplies and then reloading Starliner with about 600 pounds of research and other cargo to take back to Earth.

Starliner is one of two spacecraft NASA has hired to ferry astronauts to and form low-Earth orbit, with the other being SpaceX's Crew Dragon capsule, as part of the agency's commercial crew program.

After the aborted test in 2019 because of anomalies with the spacecraft and its software, Boeing spent more than a year tweaking the spacecraft and making sure all of its systems were working as expected.

A second launch attempt was scheduled for last summer, but was ultimately postponed due to a valve issue that cropped up while the craft was on the launch pad.

Engineers spent several months troubleshooting the valve issue before they decided to swap out Starliner's service module for a new one with a brand new propulsion system and set of valves. They also improved the valves and added nitrogen purges to keep atmospheric humidity out of the propulsion system.

That plan paid off as the craft was able to not only launch but also to complete its mission objectives at ISS and is preparing to return home.

After landing, Boeing and NASA engineers will review data from the uncrewed mission, assessing Starliner's performance, and then decide when NASA astronauts Mike Fincke and Butch Wilmore head to space on the craft's first crewed mission.

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