,<\/p>\n
In summary, the Independent Review Team\u2019s work is done, and it has begun to brief NASA officials. A final decision will then be made by NASA\u2019s senior leadership.<\/p>\n
What happens now<\/h2>\n
In preparation for Artemis II, the Orion spacecraft underwent thermal and vacuum testing this year before it will be stacked onto the Space Launch System rocket. Initially, NASA planned to begin the stacking process this month but ultimately delayed this until there was clarity on the heat shield question. The shield is already attached to the spacecraft.<\/p>\n
Most people Ars spoke to believe NASA will likely fly with the heat shield as is. Sources have indicated that NASA engineers believe the best way to preserve the heat shield during Artemis II is by changing its trajectory through Earth\u2019s atmosphere.<\/p>\n During Artemis I, the spacecraft followed a \u201cskip\u201d reentry profile, in which Orion dipped into the atmosphere, skipped back into space, and then made a final descent into the atmosphere. This allowed for precise control over Orion\u2019s splashdown location and reduced g-forces on the vehicle. There are other options, including a ballistic reentry, with a steeper trajectory that is harder on the crew in terms of gravitational forces, and a direct reentry, which involves a miniature skip.<\/p>\n A steeper trajectory would allow Orion\u2019s heat shield to be exposed to atmospheric heating and air resistance for a shorter period of time. NASA engineers believe that the cracking issues observed during Artemis I were due to the duration of exposure to atmospheric heating. So less time\u2014theoretically\u2014means that there would be less damage observed during the reentry of Orion during Artemis II.<\/p>\n Theoretically, of course, Orion\u2019s heat shield was supposed to perform nominally in response to the skip entry profile during Artemis I. Assessing the performance of the vehicle\u2019s heat shield was one of the main objectives of that uncrewed spaceflight, to ensure its safety before putting astronauts on board the vehicle.<\/p>\n While the heat shield performed its function\u2014a crew inside the Orion vehicle would have been fine\u2014it sustained significantly more damage than NASA\u2019s engineers anticipated. That\u2019s why they\u2019ve spent the better part of two years studying the issue, and it is why NASA has already delayed Artemis II from this year into September 2025.<\/p>\n ,<\/p>\n The engineers are probably right about the heat shield\u2019s performance with a steeper trajectory, but there is no way to know for sure without flying the heat shield, as designed, through such a profile. This raises a third choice: NASA could also fly the Artemis II mission without crew, testing the new life support equipment not in place for Artemis I, as well as the heat shield.<\/p>\n Each of these options would be difficult. If NASA flies the existing heat shield with a steeper trajectory, there will likely be dissenters. As observed during the Starliner deliberation process, the NASA safety community was emboldened to speak up. Similarly, some people within the NASA safety community are likely to express concerns about flying the heat shield as is after the unexpected damage on Artemis I.<\/p>\n At the same time, redesigning and rebuilding the heat shield would add years to the Artemis timeline, as would flying Artemis II without a crew. Both of these decisions would be difficult politically and financially for the space agency at a time when Congress has been inclined to cut money from NASA\u2019s budget rather than add it.<\/p>\n Whatever NASA decides, don\u2019t expect an official decision soon. No one wants to touch this political quagmire before the US presidential election, and it may slip into next year.<\/p>\n","protected":false},"excerpt":{"rendered":" Now that NASA has resolved the question of the Starliner spacecraft and its two crew members on the International Space Station, the agency faces another high-stakes human spaceflight decision. The choice concerns the Orion spacecraft\u2019s heat shield and whether NASA will make any changes before the Artemis II mission that will make a lunar flyby. […]<\/p>\n","protected":false},"author":1,"featured_media":44884,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[],"class_list":["post-44883","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/44883"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=44883"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/44883\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media\/44884"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=44883"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=44883"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=44883"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"\"](\"https:\/\/cdn.arstechnica.net\/wp-content\/uploads\/2024\/05\/orion-char.jpg\")
<\/p>\n<\/figure>\nWhy this will be difficult<\/h2>\n