SpaceX Dragon returns to International Space Station

Dragon has arrived at ISS

In April 2015, the Canadarm2 robotic arm grappled the SpaceX Dragon CRS-6 cargo spacecraft before attaching it to the International Space Station. [Photo: NASA]
In April 2015, the Canadarm2 robotic arm grappled the SpaceX Dragon CRS-6 cargo spacecraft before attaching it to the International Space Station. [Photo: NASA]

CAPE CANAVERAL, Fla. – Following its Friday launch from Cape Canaveral Air Force Station, SpaceX's Dragon cargo capsule arrived Sunday morning at the International Space Station after a nearly yearlong absence.

News partner Florida Today reports that at 7:23 a.m., British astronaut Tim Peake used the station's 58-foot robotic arm to capture the spacecraft floating roughly 30 feet away. The two vehicles were 250 miles over the Pacific Ocean west of Hawaii, flying 17,500 mph relative to the ground.

"It looks like we caught a Dragon," Peake radioed to mission controllers in Houston.

"There are smiles all around here," came the reply. "Nice job capturing that Dragon."

"Thanks," said Peake.

The Dragon visited the station a year ago, but the mission that followed last June failed to reach orbit when SpaceX's Falcon 9 rocket broke apart about two minutes after launch, due to a failure in the upper stage.

Now the Dragon has returned with nearly 7,000 pounds of cargo that includes the Bigelow Expandable Activity Module, a prototype for future space stations, and 20 mice that will be the subjects of muscle wasting studies, among other experiments.

The capsule's arrival means six different vehicles are visiting the station, only the second time that has happened, and it’s the first time a Dragon has joined an Orbital ATK Cygnus craft, NASA's other commercial resupply ship.

The Dragon's return to flight also is important because it’s the only spacecraft flying today that can return large amounts of cargo to Earth. It is expected to fly home next month with biological samples collected during former NASA astronaut Scott Kelly's recent yearlong mission and with bulky spacesuit components that engineers want to analyze on the ground.

After Friday's launch, SpaceX landed the Falcon 9 rocket's first stage on a ship down range in the Atlantic Ocean. CEO Elon Musk said the booster could return to Port Canaveral on Sunday.

Engine problem delays Atlas V again

The next launch of an Atlas V rocket has been delayed indefinitely while United Launch Alliance investigates what caused the rocket's RD-180 main engine to shut down six seconds early during its last flight, endangering the mission.

During the March 22 launch from Cape Canaveral of an Orbital ATK Cygnus cargo craft to the International Space Station, the rocket's Aerojet Rocketdyne upper stage engine fired for an extra minute to salvage a successful launch.

An Atlas V launch of the Navy's fifth Mobile User Objective System satellite had been scheduled for May 5, then moved back to no earlier than May 12. Now ULA says the mission's status is "delayed and indefinite" while the engine investigation continues.

The company plans to launch a Delta IV Heavy rocket in early June.