NASA began a nearly 50-hour-long countdown Monday afternoon for launching the moon-bound Artemis II mission, which would culminate in a launch from Cape Canaveral, Florida, on Wednesday evening.
Space agency administrators have expressed optimism about the prospects of launching on Wednesday, though it is possible any challenge would delay the launch. As of Sunday afternoon, NASA officials said they forecast an 80% chance of favorable conditions on Wednesday, though a chance of cloud cover and heavy winds could inhibit those plans.
"Our flight systems are ready, the ground systems are ready, our launch and operations teams are ready, and our flight operations team in Houston are also ready," Lori Glaze, NASA's exploration missions administrator, said during a news conference on Sunday.
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Artemis II is NASA's first crewed mission to the moon in more than 50 years. Though it will not land on the moon, the mission will take four astronauts on a lunar flyby, flying around the moon and back in a figure-eight shape.
The four members of the Artemis II crew — Reid Wiseman, Victor Glover, Christina Koch, and Jeremy Hansen — left Houston last Friday morning and are in quarantine in Cape Canaveral.
Speaking virtually with reporters on Sunday, the crew noted that while they are prepared for a launch on Wednesday, they are hedging their bets on the possibility of the launch being "scrubbed" or postponed.
"The four of us, we are ready to go, the team is ready to go, and the vehicle is ready to go," Wiseman said. "But not for one second do we have an expectation that we are going. We will go when this vehicle tells us it's ready, when the team is ready to go. So, we might go out to the pad, and we might have to try again a few more times. And we are 100% ready for that."
If the launch does not happen by Wednesday evening, NASA says the mission can launch between April 2-6. If the launch does not happen by then, the mission will have to wait until its next launch window, which begins on April 30.
The two-day countdown largely consists of tasks for crews to ensure the rocket and spacecraft are ready for the launch, most notably fueling up the rockets with liquid oxygen and hydrogen. In February, NASA conducted a successful dress rehearsal before discovering a problem with helium flow in one of the rockets, prompting a significant delay in launch. Because of the prior successful rehearsal, NASA opted not to conduct another rehearsal before an April launch.
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