The helium problem came as a surprise, arising after NASA had wrapped up the latest wet dress Thursday. And launch controllers still aren\u2019t certain what caused the hangup, though NASA Administrator Jared Isaacman said that in any case the issue must be addressed off the launchpad.<\/p>\n
NASA is now targeting no earlier than April to launch the mission, called Artemis II.<\/p>\n
\u201cThe quick work to begin preparations for rolling the rocket and spacecraft back to the VAB potentially preserves the April launch window, pending the outcome of data findings, repair efforts, and how the schedule comes to fruition in the coming days and weeks,\u201d the space agency said in a Monday blog post<\/a>.<\/p>\n NASA previously identified April 1, 3, 4, 5, 6 and 30 as potential launch days, though during a news conference<\/a> last Friday agency officials revealed they were assessing potential dates in May and June as well.<\/p>\n When the mission does take off, it\u2019s slated to carry NASA\u2019s Reid Wiseman, Victor Glover and Christina Koch and Canadian Space Agency astronaut Jeremy Hansen on a 10-day slingshot trip around the moon, marking the first time humans have traveled to deep space since the Apollo program ended in 1972.<\/p>\n One problem subsides \u2014 another emerges<\/p>\n There are numerous open questions about the feasibility of an April launch date for the mission.<\/p>\n Are there other issues hiding in the data that engineers haven\u2019t yet uncovered? How long will it take to find and address the helium problem? And will rolling the rocket back and forth aggravate NASA\u2019s notorious hydrogen issues?<\/p>\n NASA officials seemed on Friday to think that they had a handle on the SLS rocket\u2019s hydrogen leaks, a notorious problem that has plagued the Artemis program since pre-launch testing for an uncrewed 2022 test flight called Artemis I. Because hydrogen is the lightest element in the universe, it tends to leak out of anything intended to contain it. And after hydrogen seepage plagued the first wet dress rehearsal for Artemis II in early February, the space agency worked to replace two seals around the rocket\u2019s propellant lines in an attempt to better confine the fuel.<\/p>\n Those efforts had appeared to pay off when NASA moved into the second wet dress rehearsal on Thursday.<\/p>\n Still, NASA said that although it had fixed the hydrogen issue, officials weren\u2019t sure why there was some unexpected moisture near the seals that technicians replaced.<\/p>\n \u201cWhere it came from, I\u2019m not entirely sure,\u201d said Artemis launch director Charlie Blackwell-Thompson during the Friday news conference. And she said the hydrogen leaks more broadly were still a bit of a puzzle.<\/p>\n \u201cWe didn\u2019t have one thing that we could point to where we said this was absolutely it,\u201d Blackwell-Thompson said of the issue. \u201cWe had a number of contributing things, but certainly changing out the seals addressed the problem, because we had absolutely an incredible performance.\u201d<\/p>\n NASA\u2019s Artemis II Space Launch System, or SLS, rocket and Orion spacecraft, secured to the mobile launcher, is seen inside the Vehicle Assembly building on January 16 at NASA\u2019s Kennedy Space Center in Florida. – Joel Kowsky\/NASA<\/p>\n Then, the helium problem took mission teams right back to the drawing board. Helium gas wasn\u2019t flowing into the upper rocket. And no one was sure why.<\/p>\n Helium serves an important role. It\u2019s ideal for cleaning fuel lines and pressurizing tanks because it stays gaseous even at the super-cold temperatures of the rocket\u2019s propellants \u2014 liquid hydrogen and liquid oxygen \u2014 and helium is inert, meaning it won\u2019t cause any volatile chemical reactions.<\/p>\n But the helium issue forced engineers to use \u201ca backup method\u201d to keep the rocket in a safe configuration because it helps flush out explosive cryogenic fuels. As of Monday, NASA had not yet revealed why the gas had suddenly stopped flowing.<\/p>\n A rocky road to launch<\/p>\n NASA Administrator Jared Isaacman said in a post on social media that potential causes of the helium problem included a faulty filter located between ground equipment and the rocket, a misbehaving valve on the rocket, or an issue related to a \u201cquick disconnect umbilical,\u201d which is a line that is designed to rapidly detach from the rocket during takeoff. The latter two scenarios might be most likely, however, as such issues have come up before. A valve, Isaacman noted, led to helium issues in the lead up to the Artemis I<\/a> uncrewed test flight in 2022.<\/p>\n \u201cRegardless of the potential fault, accessing and remediating any of these issues can only be performed in the VAB,\u201d Isaacman said.<\/p>\n However, rolling the rocket off the launchpad and back to the VAB also raises a new slate of questions about how the hardware will fare during the 8-mile round trip, which takes hours to complete each way.<\/p>\n Launch officials previously said that the process of moving the rocket into position may be causing some of the hydrogen leaks. The slow yet grueling rollout procedure involves inching the 3.5 million-pound rocket and spacecraft on a \u201ccrawler\u201d or mobile platform and can put stress and strains on the massive vehicle.<\/p>\n \u201cThat rollout environment is very complicated,\u201d said Amit Kshatriya, NASA\u2019s associate administrator, during a February 3 news conference<\/a>.<\/p>\n Even after the helium issue is solved, NASA might need to put the SLS rocket through another wet dress rehearsal.<\/p>\n In a Monday email, a NASA spokesperson said launch controllers will review what additional tests may be needed after the rocket returns to its launchpad.<\/p>\n Whether during the next wet dress rehearsal or on launch day, mission controllers must once again keep hydrogen leaks under control \u2014 if the recently replaced seals begin to show their signature fickleness after the journey back out to the launchpad.<\/p>\n If additional issues arise during any of these steps, it could take the potential April launch windows off the table as well. And a monthslong delay wouldn\u2019t be unheard of. Notably, in the lead-up to the 2022 Artemis I mission, the SLS rocket was taken off the launchpad three times and ultimately launched about eight months after its initial rollout.<\/p>\n NASA\u2019s Artemis program is sending humans into deep space for the first time in more than five decades. Sign up for Countdown newsletter<\/a> and get updates from CNN Science on out-of-this-world expeditions as they unfold.<\/p>\n![\"NASA\u2019s](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/02\/7c57879cedb7b51eacf79261d7d1f8d0.jpeg\"\/)
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