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Countdown begins for Artemis II 'wet' rehearsal

The Artemis II spacecraft, with a giant orange rocket, docked at a launch padGetty Images

Will it be all systems go for Artemis II?

All eyes are on the Kennedy Space Center in Florida over the next couple of days, as Nasa prepares for a practice launch of Artemis II.

It's called a wet rehearsal, and it'll see the team do a full run through of what will be happening on the actual launch day, like a dress rehearsal in a school play!

The reason it's 'wet' is because the tanks of the rocket will be filled with real liquid fuel, but unlike the launch, Artemis II won't be taking off.

Nasa are hard at work to get everything ready for the 'simulated launch time' - when the four hour practice launch will begin - of 1:30am UK time on Friday 20 February.

More on Artemis:

Why was the last wet rehearsal cancelled?

A night time photo of Artemis II illuminated by lights on the launch padReuters

There were problems with the last wet rehearsal at the Kennedy Space Center

Nasa have already attempted a wet rehearsal, but this was cancelled because of a hydrogen leak at the launch pad.

After it was stopped, Nasa boss Jared Isaacman wrote on social media that: "These tests are designed to surface issues before flight and set up launch day with the highest probability of success.

"We will only launch when we believe we are as ready to undertake this historic mission," he added.

The delay in the wet rehearsal has meant that the actual launch date of Artemis II has been pushed back too.

What happens in a wet rehearsal?

A large sign reading Artemis with a rocket in the backgroundGetty Images

This launch is part of Nasa's Artemis program, which hopes to put humans back on the Moon and build a space station there

Nasa's launch controllers have already set up at the Launch Control Centre and have begun a 50 hour countdown to the practice launch.

They'll load the liquid fuel into the rocket, and drain the tanks too, rehearsing lots of parts of the launch.

This includes pausing and starting the countdown at different points, which could happen in a real launch if the team run into any technical problems or bad weather.

The Artemis II astronauts won't be there this time, but the team will practise closing the spacecraft's hatches as if the crew were inside.

When will Artemis II launch?

Astronauts wearing bright orange spacesuits walk out onto a space centre in FloridaReuters

The Artemis II crew - Victor Glover, Jeremy Hansen, Reid Wiseman, and Christina Koch - have already taken part in a practice countdown

After the wet rehearsal, Nasa scientists will look back on what happened and review if it was successful.

If the results are looking good, Nasa will plan a second wet dress rehearsal and set a launch date in place.

The earliest date for Artemis II to launch is Friday 6 March, but it could be on any of these dates within two launch windows:

  • 6, 7, 8, 9, or 11 March

  • 1, 3, 4, 5, 6, or 30 April