By Joey Roulette
COLORADO SPRINGS, Colo., April 16 (Reuters) – Astronauts who flew around the moon and back on NASA’s landmark Artemis II mission said their re-entry into Earth’s atmosphere went smoothly, but the mission’s commander described some cracks in the Orion capsule’s critical heat shield.
Four Artemis II astronauts touched down in the Pacific Ocean last Friday, capping a nearly 10-day test flight that saw them reach the furthest point in space as their gumdrop-sized Orion capsule orbited the far side of the moon.
Re-entering Earth’s atmosphere at about 32 times the speed of sound, the high-stakes mission culmination was an important test of the Lockheed Martin-built Orion capsule before NASA plans to re-use it for another pre-lunar landing flight into Earth orbit next year.
“We came in fast, and we came in hot,” Artemis II mission commander Reid Wiseman told reporters at the crew’s first press conference since returning to Earth.
In the months following the flight, NASA engineers will use troves of data to illustrate how well the Orion vehicle performed. They are likely to pay close attention to the capsule’s heat shield, a critical barrier that protects the crew from temperatures of up to 5,000 degrees Fahrenheit (2,760 degrees Celsius) during descent from space.
On the 2022 Artemis I uncrewed mission, Orion’s heat shield suffered more damage than NASA expected, showing small cracks and some layers burned during reentry, leading to two years of intensive research.
NASA did not upgrade the heat shield, but it did change the angle and trajectory in which the Artemis II crew entered Earth’s atmosphere to reduce the heat.
Wiseman said he and mission pilot Victor Glover “saw two moments of maybe four losses” during re-entry.
When they examined the capsules aboard the Navy ship that retrieved them from the ocean, Wiseman said he saw “a little char loss on the shoulder,” referring to the edge of the heat shield.
Fall at least 32 times the speed of sound
Photographs of the capsule after the Artemis II crew’s return showed an unusual white mark on the edge of the heat shield, but NASA Administrator Jared Isaacman downplayed the concern, saying it had behaved similarly in high-temperature ground tests.
“No piece is missing,” Isaacman told Reuters on Monday, adding that he had seen underwater photos of the heated shield bobbing in the ocean shortly after the splashdown. “The heat shield performed as expected, and I’m thrilled, because now we’ve talked about it.”
Glover described the crew’s re-entry as “a very intense 13 minutes and 36 seconds”.
At the time, NASA officials said that the crew’s maximum speed on re-entry was 24,664 mph (39,692 km/h), or about Mach 32, 130 mph, the record set by Apollo 10 in 1969 for the fastest manned flight.
But Glover told reporters Thursday that Orion’s onboard screens showed they had reached Mach 38.89, or 29,839 mph. He added that NASA could release a new number “when we figure it out” because it’s challenging to measure speed in space.
After atmospheric friction slowed them down, the initial set of parachutes slowed them down even more after entering Earth’s lower atmosphere before releasing in front of a final set of chutes that brought them to sea level at 17 mph.
When the initial parachute set was cut, Glover said, “We’re back in free fall… I’ve never been BASE jumping, I’ve never been skydiving, but if you fall backwards off a skyscraper, that’s what it feels like.”
The agency’s Orion space launch system is a capsule launched from a rocket to Earth and a capsule to send humans into space, future crews will use the capsule to dock with lunar landers built by Elon Musk’s SpaceX and Jeff Bezos’ Blue Origin that will land them on the moon.
Those landers will be tested in Earth orbit for the first time on the Artemis III mission, planned for next year.
In his personal opinion, Wiseman said, “They could put the Artemis III Orion in the space launch system tomorrow and launch it and the crew would be in good shape.”
(Reporting by Joey Roulette; Editing by Jamie Freed)
