NASA's first crewed trip around the moon in more than 50 years is coming down to 13 or 14 very intense minutes, NBC News reports. The four Artemis II astronauts are due to slam into Earth's atmosphere Friday evening in their Orion capsule, with a planned Pacific splashdown off San Diego at 8:07pm ET after 10 days in space. Those final minutes, starting around 7:53pm ET, will see Orion hit speeds near 24,000mph and temperatures around 5,000 degrees Fahrenheit and astronauts experiencing G forces equivalent to nearly four times gravity's pull on Earth, with a six-minute communications blackout expected as plasma surrounds the capsule.
Re-entry is always the dicey part of a mission, but this one carries an added complication: Orion's heat shield. After the uncrewed Artemis I flight in 2022, NASA discovered unexpected cracking and char loss in the shield's outer layer. The fix for future flights comes too late for this already-built capsule, so engineers instead redesigned the return path: a shorter, steeper descent that limits time in the hottest zone. Says flight director Jeff Radigan, "We have to hit that angle correctly. Otherwise, we're not going to have a successful re-entry." As the Los Angeles Times reports, it's a new re-entry technique that is yet untested in the real world.
NASA officials insist they have "high confidence" in the shield, though at least one former astronaut has publicly argued the mission shouldn't have flown with the current design; he tells the New York Times his own personal estimate puts the chances of disaster at 5%. A retired NASA heat shield engineer says he believes the decision to fly the mission as-is was "reckless." But another former NASA astronaut and scientist says discussions and meetings with NASA convinced him, and he says he assured the Artemis II commander that he believes NASA did a good job of risk mitigation. "I would never have rubber-stamped it for NASA's sake," he says.
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