The SpaceX Dragon cargo ship arrived at NASA's International Space Station (ISS) on Sunday. It carries with it 2.5 tons of supplies and experiment hardware.

The spacecraft, which lifted off from Launch Complex 40 at the Cape Canaveral Air Force Station in Florida, hauled nearly 2.5 tons of supplies and experimental hardware. Dragon set out on its journey at about 3:25 p.m EDT. The craft rendezvoused with the station Sunday morning before Commander Koichi Wakata and Flight Engineer Rick Mastracchio used the Canadarm2 robotic arm to capture it at 7:14 a.m. for berthing at the Harmony module.

"The Easter Dragon is knocking at the door," astronaut Randy Bresnik radioed to the crew from Mission Control in Houston, as reported by Reuters.

Dragon's arrival will help provide goods for scientific experiments focusing on growing plants in space, testing laser optics technology to communicate with Earth, human immune system function in microgravity and Earth observation. SpaceX Dragon also brought in its cargo a pair of humanoid robotic legs that can be used for future spacewalks.

SpaceX used this resupply mission as an opportunity to test its reusable rocket launch. The company tried to recover the Falcon 9 by a reentry to the ocean but failed the ocean splashdown. Despite its failure, CEO Elon Musk remained optimistic and considered the test successful nonetheless, as their experiment allowed them to control the boost stage of the launch at a zero roll level. Musk reiterated that it is the uncontrolled roll that usually destroys the rocket.

"I heard reports of 13 to 20-foot wave heights. It's really pretty crazy out there," Musk stated during a post launch press conference, as quoted by Space.com. "In fact, the [retrieval] boats weren't able to get close because of the heavy seas. It's unlikely that the rocket was able to splash down successfully."

Meanwhile, the Expedition 39 crew prepared for a scheduled 2.5 hours of spacewalk on Wednesday, to replace a defective backup computer relay box. The spacewalk will be aired in NASA TV at 9:20 a.m.