A commercial cargo ship, operated by private U.S. space firm SpaceX, left the International Space Station on Friday morning, carrying back more than a ton of cargo and science samples, including 12 mice.

The unmanned Dragon spacecraft was detached from the Earth-facing side of the space station's Harmony module Thursday night and then released from the orbital laboratory's robotic arm at 6:11 a.m. EDT (1011 GMT), U.S. space agency NASA said.

The capsule, packed with 3,000 pounds (1,360 kg) of cargo and science samples, is currently scheduled to splash down in the Pacific Ocean about 11:47 a.m. EDT (1547 GMT), approximately 326 miles (525 km) west of Baja California, Mexico.

Following the splashdown, Dragon will be recovered from the ocean and put on a ship for transportation to a port near Los Angeles, where some cargo, including research payloads, will be removed and returned to NASA within 48 hours, the space agency said.

Dragon delivered numerous science experiments on July 20 that space station astronauts immediately unloaded and began working on. NASA said one of those experiments returned aboard Dragon is a heart cells study, which explored how microgravity affects human heart cells.

Another experiment NASA mentioned in particular is the mouse epigenetics study, which explored how microgravity alters gene expression and DNA in 12 male mice.

Currently, Dragon is the only resupply spacecraft able to return to Earth intact.

Source : XINHUA