The reentry marked the most critical stage of Orion’s journey, testing whether the newly designed heat shield could withstand atmospheric drag expected to raise the temperature outside the capsule to nearly 2,760 degrees Celsius.
It was also a test of the advanced guidance and propulsion systems used to steer the moon’s capsule to the correct reentry point and through descent, holding the spacecraft at just the right angle to avoid burning up.
“It’s essentially like throwing a soccer ball 300 yards and hitting a penny,” said Eric Coffman, senior manager of Orion propulsion at Lockheed Martin Corp, which built Orion under contract with NASA, ahead of its return.
An internal navigation and control system directs 12 onboard thrusters, mounted in recessed positions along the capsule’s base, to fire bursts of propellant as needed to keep the capsule correct and on course, he said.
The heat, speed, and forces exerted on Orion on its return from the moon surpassed those produced by spacecraft making more routine descents from the International Space Station (ISS) or other flights from low Earth orbit.
NASA officials had emphasized the experimental nature of the Artemis I mission, which marked the first launch of the Boeing-built SLS and the first paired with Orion, which previously flew a short two-runway test run on a smaller Delta IV in 2014. rocket was launched.
Although the capsule experienced some unexpected communication outages and an electrical problem during its trip around the moon, NASA has so far given high marks to the performance of both SLS and Orion, boasting that they exceeded the US space agency’s expectations.
If Artemis I is considered a success, a crewed Artemis II flight around the moon and back could take place as early as 2024, followed within a few years by the program’s first lunar landing of astronauts, one of them a woman, with Artemis III.
Compared to Apollo, born of the Cold War space race between the US and the Soviet Union, Artemis is more science-driven and broadly based, enlisting commercial partners such as Elon Musk’s SpaceX and the space agencies of Europe, Canada and Japan.
It also marks a major turning point for NASA as it redirects its human spaceflight program beyond low Earth orbit after decades of focusing on space shuttles and the ISS.
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