NASA's Artemis I launch is delayed once again, what's wrong with SLS?

NASA's first SLS rocket launch is delayed once again.

NASA announced on Saturday, April 16, that it will roll its Space Launch System (SLS) back from the launch pad for repairs.

In a statement, the U.S. space agency said it plans to roll the SLS to the Vehicle Assembly Building (VAB) "due to upgrades required at an off-site supplier of gaseous nitrogen used for the test". Problems related to the supply of gaseous nitrogen had scuppered two previous countdown rehearsals.

NASA rolled SLS out to the Launch Complex 39B on March 17 using its Crawler-Transporter 2 vehicle. The space agency should announce a revised schedule today for its SLS launch, which will kickstart its bid to send astronauts back to the Moon. NASA announced that it will hold a media teleconference today, April 18, to provide further information on SLS.

Returning to the Moon

NASA also announced it will use the delay postponement to repair a faulty helium check valve in the upper stage of SLS as well as a hydrogen leak detected on April 14. SLS's maiden launch has been hit by a long string of delays in recent months. It's a state of affairs that has led one industry insider to suggest the space agency is "shitting the bed" over the fact that its technology is so far behind that of SpaceX's Starship launch vehicle.

SLS is NASA's most powerful rocket yet, though it's actually slightly shorter (322 ft) in height than the Saturn V rocket (363 ft) that launched the Apollo 11 mission. While Saturn V was able to carry 7.5 million pounds into space, SLS has the capacity to launch 8.8 million pounds.

NASA's first operational SLS launch, for mission Artemis I, will take the uncrewed rocket around the Moon. Artemis II will send a crew of NASA astronauts around the Moon, while Artemis III will perform the first crewed Moon landing since the 1970s. Artemis III, however, will be carried out using a SpaceX Starship launch vehicle, after NASA signed a contract worth $2.9 billion with the private space firm to send the next astronauts to the Moon.