'Welcome home, Artemis': Crew celebrates historic 10-day moon mission

It will take Orion about 14 minutes to travel the 400,000 feet from space to splashdown off the coast of San Diego.

Everyone inside the spacecraft will be laser-focused on monitoring the onboard systems during their descent through the atmosphere, according to retired NASA astronaut Barry "Butch" Wilmore.

The astronauts train for "all types of failures," so their mindset is just to concentrate on the jobs at hand, he said.

"You can't let apprehension involve you in those time frames," Wilmore told ABC News. "You have to focus on your task, whatever that might be, and you have to perform because if you don't, the consequences are pretty dire."

-ABC News' Briana Alvarado

The Orion crew module will be falling to Earth at over 24,000 mph when it encounters the atmosphere. As the atmosphere thickens, friction will slow the spacecraft. It will also create a lot of heat -- up to 5,000 degrees Fahrenheit, which is more than twice as hot as lava from a volcano -- turning Orion into a fireball.

Orion's heat shield, located on the underside of the spacecraft, will protect the spacecraft and its crew from the intense temperatures of reentry. Onboard maneuvering jets ensure Orion maintains the orientation required to keep the heat shield pointed toward Earth during reentry.

"Importantly, there's this coating on the outside that's meant to melt upon being heated rather than absorbing that energy," ABC News contributor and astrophysicist Hakeem Oluseyi said. "So, it's much in the same way that a car is meant to crumple in an accident rather than being a stiff object. You want to dissipate that energy. You need the energy to go somewhere that is not inside the capsule."

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How Orion’s heat shield can withstand up to 5,000 degrees on reentryABC News contributor and astrophysicist Hakeem Oluseyi discusses the physics and science behind the Artemis II crew’s reentry to Earth.

ABCNews.com

Artemis II Commander Reid Wiseman gave a shoutout to teams around the world for their role in creating the Orion spacecraft.

"We just want to give a huge shoutout to that ESA [European Space Agency] Airbus team, to our friends in the Netherlands and Germany and at the Glenn Research Center," Wiseman said. "This vehicle powered us and propelled us from the Earth to the moon and back with extreme precision, and we are excited to be a part of your team."

-ABC News' Briana Alvarado

Orion completed its final return correction burn successfully at 2:53 p.m. ET.

This burn ensures the spacecraft maintains the proper trajectory back to Earth.

The crew and service module will separate and reveal the Orion heat shield at 7:33 p.m. ET.

-ABC News' Matthew Glasser