CHICAGO (CBS) -- It's a historic day for NASA's Artemis one mission.

The uncrewed Orion spacecraft is on its last day in space.

It will splash down off the coast of Mexico around 11:39 a.m. Chicago time.

As the spacecraft comes back earth's atmosphere will initially slow it down to 325 miles per hour.

NASA created an animation that shows the process.

A system of parachutes will slow it even more to a splashdown speed of 20 miles per hour.

Orion was launched into space by the powerful Artemis rocket on Nov. 16.

It did a fly-by of the moon on Dec. 5 before making the journey back home to earth.