SpaceX's unmanned Dragon spacecraft left the International Space Station and returned to Earth on Saturday after a month in orbit, NASA said.
Astronauts at the orbiting lab manipulated the space station's robotic arm to detach the Dragon on time, at 9:57 am (1357 GMT), in what the US space agency called a "very clean release."
The capsule splashed down five and a half hours later, at 3:39 (1939 GMT) in the Pacific Ocean, near the Mexican coast, slowed by three enormous parachutes.
The unmanned craft, which has been docked in orbit since September 23, ferried back some 3,200 pounds (1,450 kilograms) of materials, including results from experiments conducted on the space station.
It also carried crew supplies, hardware, and computer resources.
The SpaceX vessel is the only spacecraft currently capable of returning with cargo. Its last mission to ISS was in April.
It had delivered more than 5,000 pounds (2,200 kilograms) of cargo, including freeze-dried meals, 20 live lab mice and a 3D printer, in its fourth contracted mission to the orbiting lab.
The lab mice are the first live mammals to hitch a ride aboard a commercial cargo ship, and they are enclosed in a NASA-made research cage for studying the effects of weightlessness on their bodies.
The 3-D printer is the first of its kind to demonstrate how the technology can be used in space, even without gravity to assist the process.
The Dragon return Saturday kicks off a week of heavy traffic to and from the orbiting science lab.
Monday evening, Orbital Sciences is scheduled to launch its unmanned Cygnus capsule from the Wallops Island space center, on the coast of Virginia, and should arrive November 2 at ISS at the same dock that held Dragon.
And on Wednesday, a Russian cargo ship, Progress, is set to take off for ISS, taking the place of a sister Russian vessel that is to break away from the orbiting station and return to Earth on Monday.
And looking a few weeks further, three of the six ISS crew members are already preparing to leave the lab after 165 days in orbit. They are set to ride in a Russian Soyuz craft on Sunday, November 9th.
Their three replacements, a Russian and two Americans, should arrive on November 23.
NASA lost its ability to reach the space station when the shuttle program ended in 2011 after 30 years.
The US space agency has helped fund private companies in the race to restore US access to the ISS.
In 2010, SpaceX became the first private company to send a spacecraft to the ISS.
The company is run by Internet mogul Elon Musk, who built his fortune by co-founding PayPal. He also runs Tesla Motors.