Editor's note: SpaceX's Inspiration4 crew successfully launched into orbit at 8:02 pm ET from NASA's Pad 39A at the Kennedy Space Center. You can see a launch replay above and the full webcast below. Read our launch wrap here.
SpaceX's Inspiration4 mission is ready to launch to Earth orbit on Wednesday (Sept. 15), and you can watch the historic liftoff live.
The launch webcast will start on SpaceX's YouTube channel Wednesday at 3:45 p.m. EDT (1945 GMT) and will also stream here at Space.com, courtesy of SpaceX. The five-hour launch window at NASA's Kennedy Space Center in Florida opens at 8:02 p.m. EDT (0002 GMT on Thursday, Sept. 16).
In case you missed it, you can also hear virtually from the four crewmembers of Inspiration4, the first all-civilian mission to Earth orbit, during a press conference from SpaceX held on Tuesday. That event aired on SpaceX's YouTube channel.
Live updates: SpaceX's Inspiration4 private all-civilian orbital mission
More: Inspiration4: When to watch and what to know
At 7 p.m. EDT (2300 GMT), Netflix will host a live "Countdown to Launch" event with veteran astronauts and celebrities watching the launch. You can watch that live below.
Flying into space will be billionaire Shift4 Payments founder Jared Isaacman (who booked the mission and paid for all the seats); physician assistant Hayley Arceneaux; geoscientist, analog astronaut and science communicator Sian Proctor; and engineer Chris Sembroski. Arceneaux came on board through a personal invitation from Isaacman, while Proctor and Sembroski won Inspiration4-related contests.
Full details about the Inspiration4 mission are available in this Space.com explainer discussing the crew biographies and their goals for the three-day mission.
If the launch is delayed for any reason, a backup opportunity is available opening at 8:05 p.m. EDT on Thursday (Sept. 16; 0005 GMT on Friday, Sept. 17), Inspiration4 representatives wrote in a recent press release. Weather conditions are currently 70% favorable for Wednesday's prime launch window.
The cargo for Inspiration4 will include a suite of health-related experiments, fitting in with the mission's greater theme to raise awareness and money for St. Jude Children's Research Hospital in Memphis.
The SpaceX Crew Dragon capsule launching Wednesday will also include a few other unique items, such as a Martin Guitar ukulele that Sembroski will play in space, and a never-before-released performance of "Time in Disguise," a song from the Grammy Award-winning rock band Kings of Leon.
The performance is going into orbit as a non-fungible token (NFT), which is a virtual item that can be sold on certain marketplaces. The crew also plans to fly 50 art NFTs from 50 different artists and several other space-related things, listed here.
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