SpaceX's Dragon capsule has arrived at the International Space Station two days after blasting off Wednesday from the Brevard County coast.
Italian astronaut Samantha Cristoforetti and NASA astronaut Terry Virts used the space station's robotic arm to capture Dragon at 6:55 a.m.
The capsule delivered two tons of cargo to the orbiting outpost, including an espresso machine for astronauts, along with some mice that will be used to study microgravity's impact on aging.
Also on the capsule are experiments for NASA astronaut Scott Kelly, who recently started his mission to spend an entire year living in space. NASA will study both the physical and psychological effects of spending a year in microgravity.
One experiment loaded in the capsule will study how Kelly's vision changes over the next year.
More than half of American astronauts have experienced vision changes, because without gravity, body fluids shift up to the head, putting pressure on the brain and causing changes to the eyes.
"We need to get a handle on those types of problems now, so that we can protect the crew in the future, because that's directly needed in terms of crew performance, our ability to see," said Marshall Porterfield, with NASA's Space Life and Physical Sciences Research and Applications Division.
That will also be necessary to understand if we ever send astronauts to Mars.
The capsule will stay at the International Space Station for about five weeks before splashing down in the Pacific Ocean with more than 3,000 pounds of science experiments and trash.