Orion's crew module has separated from the European Service Module, exposing the heat shield that will protect the spacecraft during its high-speed travel through the Earth's atmosphere.

That shield will withstand temperatures of up to 5,000 degrees Fahrenheit during the high-speed entry.

U.S. Navy divers could be seen preparing to deploy from the well deck of the USS John P. Murtha, which will retrieve the crewmembers and NASA's Orion spacecraft once they splash down off the coast of San Diego.

Members of the crew can be seen in their orange spacesuits now while at the controls of the Orion spacecraft ahead of their reentry.

Here's a look at the "carefully timed sequence" of the final stages of Orion's descent, according to NASA. All times Eastern.

7:33 p.m.: Orion's crew module will separate from the European Service Module, exposing the heat shield that will protect the spacecraft as it travels through the Earth's atmosphere.

7:37 p.m.: Orion will perform an 18-second raise burn that fine-tunes the reentry angle of the spacecraft to minimize the time the heat shield will experience high temperatures.

7:53 p.m.: Orion will make first contact with the upper atmosphere, beginning a planned 6-minute communications blackout. The crew is expected to experience up to 3.9 Gs as the spacecraft travels nearly 35 times the speed of sound.

7:59 p.m.: NASA will regain communications with the crew.

8:03 p.m.: At around 22,000 feet in altitude, drogue parachutes will deploy to help slow the capsule ahead of splashdown.

8:04 p.m.: Three main parachutes will deploy at around 6,000 feet, reducing Orion's speed to less than 136 mph.

8:07 p.m.: Orion will splash down in the Pacific Ocean, off the coast of San Diego, having slowed to 20 mph.

Weather is expected to be a green light at the Kennedy Space Center in Cape Canaveral, Florida, for the Artemis II mission to launch.

The two-hour window from 6:24 to 8:24 p.m. will feature temperatures in the mid to low 70s, forecasters say.

Winds will be between 8 and 16 mph, with a rare gust up to 20 mph, max.

There will be a mix of clouds and clear skies with no forecast chance for rain or lightning.

-ABC News’ Kenton Gewecke