How To Watch NASA's Mega Moon Rocket Dress Rehearsal After It Was Scrapped

NASA was forced to delay the "wet" dress rehearsal for the launch of its 322-foot-tall rocket, the Space Launch System (SLS), on Sunday due to safety issues.

The space agency said late yesterday that it is now targeting Monday, April 4, to resume the practice countdown for the Artemis I mission, which will take place at the Kennedy Space Center in Merritt Island, Florida.

NASA said the launch control team is planning to resume the countdown prior to propellant loading at around 7 a.m. EDT on Monday, with the dress rehearsal test planned for 2:40 p.m. EDT

If you would like to watch today's dress rehearsal—assuming there are no further snags—NASA is providing a live video stream of the SLS at the launch pad that can be viewed on the Kennedy Space Center Newsroom YouTube channel.

The test was stopped yesterday due to the loss of ability to pressurize the rocket's mobile launcher using two fans. A technical issue with the fans meant that they were not working properly.

The fans are needed to provided positive pressure to the enclosed areas within the mobile launcher in order to prevent the build-up of hazardous gases. Without the ability to do this, operators were unable to safely proceed with remotely loading propellants into the rocket.

On Saturday, the launch site was also affected by severe thunderstorms, during which protective towers around the rocket and launcher were struck by lightning. While this caused a delay in preparations for the dress rehearsal, NASA said no launch systems had been damaged and the countdown could continue.

NASA said one of the three nearly 600-foot-tall lightning towers was struck. These towers form a defensive system that works to protect the rocket from lightning strikes.

On Sunday, Jim Free, associate administrator for NASA's Exploration Systems Development Mission Directorate, said in a tweet: "I'm always impressed by the discipline and the toughness of our #Artemis team. The weather tested us, and they persevered. While we faced challenges today, the team will work through them, and we'll try again tomorrow."

When will SLS launch?

Artemis is the name of NASA's program to return astronauts to the moon and establish a sustainable presence on the lunar surface, paving the way for future human missions to Mars.

The SLS, which NASA says is the most powerful rocket ever built, is a key part of this program, alongside the Orion spacecraft that it will launch into space.

The wet dress rehearsal is the last major test before the SLS launches on its first unmanned test flight—Artemis I—which could potentially take place this summer and is expected no earlier than June 2022.

During the mission, the Orion capsule will travel around the moon without a crew before returning to Earth.

The wet dress rehearsal will prepare the Artemis I team for the real thing, enabling them to run through operations to load propellant into the rocket's tanks and conduct a full launch countdown, among other procedures.

The rehearsal is described as "wet" because it will involve the loading of more than 700,000 gallons of cryogenic—or super cold—propellants, such as liquid hydrogen and liquid oxygen, into the rocket at the launch pad.

NASA's Space Launch System
NASA's Space Launch System rocket with the Orion spacecraft aboard is seen atop a mobile launcher at Launch Complex 39B, on Friday, March 18, 2022, after being rolled out to the launch pad for the first time at NASA's Kennedy Space Center in Florida. Aubrey Gemignani/NASA via Getty Images