The last 13 minutes of the historic 10-day NASA moon mission, the journey back to Earth, were the most critical for the four astronauts \u2013 Reid Wiseman, Victor Glover, Christina Koch, and Jeremy Hansen \u2013 aboard the Artemis II flight. It was a test of the Orion spacecraft’s heat shield.<\/p>\n
\u201cIt\u2019s 13 minutes of things that have to go right,\u201d Artemis II<\/a> flight director Jeff Radigan said at a news briefing on Thursday.<\/p>\n NASA knew there was a problem with the Orion spacecraft, which the crew named Integrity, even before it left the Kennedy Space Center launchpad on April 1.<\/p>\n Orion had sustained an unexpected level of scorching and stress on re-entry during its 2022 test flight. Engineers had discovered over 100 locations on the heat shield that had cracked and broken off during reentry.<\/p>\n NASA engineers altered the descent trajectory for Artemis II to reduce heat buildup and lower the risk to the capsule and its crew.<\/p>\n Also Read | Trump congratulates Artemis II crew for perfect landing \u2014 \u2018Next step, Mars!\u2019<\/a>Artemis II splashdown<\/p>\n The crew’s homecoming cleared a critical final hurdle for the Lockheed Martin-built Orion spacecraft<\/a>, proving it would withstand the extreme forces of re-entry from a lunar-return trajectory.<\/p>\n It followed a white-knuckle, 13-minute fiery plunge through Earth’s atmosphere, generating frictional heat that sent temperatures on the capsule’s exterior soaring to some 5,000 degrees Fahrenheit (2,760 degrees Celsius).<\/p>\n At the peak of re-entry stress, as expected, intense heat and air compression formed a red-hot sheath of ionised gas, or plasma, that engulfed the capsule, cutting off radio communications with the crew for several minutes.<\/p>\n The tension broke as contact was re-established and two sets of parachutes were seen billowing from the nose of the free-falling capsule, slowing its descent to about 15 mph (25 kph) before Orion gently hit the water.<\/p>\n Also Read | Artemis II splashdown LIVE: Astronauts emerge one-by-one from their capsule<\/a>How did NASA make it work<\/p>\n