CAPE CANAVERAL, Fla. >> The commercial cargo ship Dragon left the space station on Sunday, heading home with nearly 2 tons of science experiments and old equipment.

After a one-month visit, the SpaceX cargo ship was set loose for its return to Earth. The astronauts released it using the International Space Station’s big robot arm, as the craft zoomed more than 260 miles above the South Pacific.

“It’s moving away,” reported astronaut Steven Swanson, the station’s commander.

“Nicely done,” said Mission Control.

Swanson later added: “Very nice to have a vehicle that can take your science, equipment and maybe someday even humans back to Earth.”

The Dragon capsule was bringing back 3,500 pounds of gear. The California-based SpaceX company was aiming for a Pacific splashdown in midafternoon, Eastern Daylight Time, about 300 miles off Mexico’s Baja California peninsula. It’s the only supply ship capable of safely returning items.

NASA is paying SpaceX and Virginia-based Orbital Sciences Corp. to make station deliveries. SpaceX also is competing for the right to ferry station astronauts, perhaps as early as 2017.

The Dragon rocketed to the space station on April 18 with a full load and arrived at the orbiting lab two days later.