(Reuters) – NASA will return Boeing’s (NYSE:) failed Starliner capsule to Earth without astronauts Butch Wilmore and Suni Williams, who are scheduled to return to Earth early next year on a SpaceX vehicle, NASA Administrator Bill Nelson said on Saturday.

Starliner launched its first two astronauts, both former military test pilots, into space on June 5 as a crucial test before it can receive NASA approval for routine flights. But what was supposed to be an eight-day mission docked with the ISS has been delayed for months after the capsule leaked and some of its thrusters failed.

Below is a summary of the major events during Starliner’s journey into space over the past few years:

September 4, 2015 – Boeing unveils an assembly plant for its first commercial spacecraft, which NASA plans to use to fly crews to the ISS.

November 4, 2019 – Boeing reports that one of its three parachutes failed to deploy during a crucial unmanned test of the Starliner.

December 20, 2019 – Boeing successfully launches its new astronaut capsule on a debut unmanned journey to the ISS.

December 22, 2019 – The spacecraft makes a “bullseye” landing in the New Mexico desert.

January 7, 2020 – NASA and Boeing are investigating a software error that prevented the unmanned capsule from arriving at the ISS in December 2019.

February 6, 2020 – NASA’s review board says Boeing narrowly missed a “catastrophic failure” during the December flight.

August 25, 2020 – The first crewed Starliner mission is tentatively scheduled for 2021, as Boeing aims to complete software and test hardware production by then.

Oct. 7, 2020 – Chief astronaut for Starliner’s crewed flight to the ISS, Chris Ferguson, steps down due to family priorities. He is replaced by Wilmore.

July 29, 2021 – A space station accident forces NASA to postpone the launch of Starliner.

August 3, 2021 – Boeing postpones Starliner launch after new failure.

August 13, 2021 – Boeing sends the spacecraft back to the factory to fix a valve problem, delaying the launch date until at least mid-October, if not later.

May 19, 2022 – The Starliner capsule is launched for an unmanned test flight to the ISS.

May 20, 2022 – The Starliner capsule, without astronauts on board, docked with the ISS for the first time.

Aug 25, 2022 – Boeing announces that the first Starliner mission with astronauts is scheduled to take place in early 2023.

June 1, 2023 – Boeing says it is winding down final preparations for the first crewed Starliner test flight into space, scheduled for July 2023, after discovering two safety risks with the spacecraft.

May 3, 2024 – Boeing is set to launch the first Starliner space capsule with a crew of humans into orbit the following week, after a year-long delay.

May 6, 2024 – The first crewed test flight of the new Starliner space capsule has been postponed after the planned May 6 launch was halted due to a malfunction of the Atlas (NYSE:) V rocket.

May 7, 2024 – NASA reports that the new target launch date for the mission has been set as early as May 17.

May 14, 2024 – Boeing reports that the Starliner mission has been delayed again — until at least May 21 — due to a problem with the spacecraft’s propulsion system.

May 17, 2024 – NASA and Boeing are again delaying the launch of the Starliner crew capsule to monitor for helium leaks. The launch is now scheduled for May 25.

May 21, 2024 – NASA is again postponing the first crew flight to spend more time evaluating a helium leak in the spacecraft’s propulsion system.

May 22, 2024 – NASA and Boeing are targeting a June 1 launch date.

June 1, 2024 – A second attempt to launch the Starliner with astronauts on board was automatically halted by a computer-controlled system minutes before liftoff.

June 2, 2024 – Boeing and NASA are targeting a June 5 launch date.

June 5, 2024 – The Starliner astronaut capsule has been successfully launched from Florida with two astronauts on board. Docking with the ISS is scheduled for June 6.

June 6, 2024 – The Starliner capsule and a first crew of two NASA members have safely docked with the International Space Station.

June 11, 2024 – NASA and Boeing expect the Starliner capsule to return as early as June 18, later than previously planned, citing repairs to defective capsule components and weather conditions.

June 21, 2024 – NASA is further delaying the Starliner’s return to Earth to allow more time to assess the technical issues that occurred.

June 27, 2024 – NASA says it will continue to evaluate the performance of Starliner’s propulsion system with Boeing.

Aug. 7, 2024 – NASA says the two astronauts could return to SpaceX’s Crew Dragon in February 2025 if it is still deemed too unsafe to return Starliner to Earth.

Aug 24, 2024 – The Starliner capsule will return to Earth without astronauts Butch Wilmore and Suni Williams on board, after NASA chief Bill Nelson said the duo should return in a SpaceX vehicle early next year.