Splashdown northwest of Key West, Florida, will close out a mission highlighted by the first non-government civilian spacewalk.

The Spaceship Neptune pressurized capsule took a six-hour journey to about 100,000 feet above the Earth's surface before descending for a splashdown.

SpaceX's Polaris Dawn early Sunday splashed down in the Gulf of Mexico after a five-day mission that included the world's first commercial spacewalk and humans the farthest from Earth since the 1970s.