The Dragon space capsule, which has launched a new era of commercial spaceflight, completed its first tests before its scheduled docking at the International Space Station, NASA said on Wednesday.
The test flight of US company SpaceX's capsule, which launched atop a Falcon 9 rocket on Tuesday, aims to show that industry can restore US access to the ISS after NASA retired its space shuttle fleet last year.
"So far everything is going as planned," said NASA spokesperson Kelly Humphries of the Johnson Space Center in Houston, Texas, that directs all ISS missions and activities. He pointed to a "sense of optimism" among the mission control team.
Humphries said the capsule has completed the first part of its demonstration flight, including navigating with the Absolute GPS system, an abort demonstration and a demonstration of free drift, a mode often used when interacting with the ISS.
The mission is set to include a fly-by and berthing with the station this week, before the capsule returns to Earth at the end of this month.
On Thursday, the spacecraft's sensors and flight systems are to undergo a series of tests to see if it is ready to berth, including a complicated fly-under at a distance of about 2.5 kilometres.
If NASA gives the green light, the Dragon will then approach the ISS on Friday in an attempt to berth with the station.
If the Dragon capsule successfully docks at the orbiting outpost, it will mark a new era in space transportation with commercial firms playing a growing role in space travel.
The astronauts on board the ISS will manoeuvre the station's robotic arm to help capture the capsule and attach it to the orbiting research outpost.
The hatch of the Dragon is set to open on Saturday to unload 521 kilograms of cargo for the space lab and restock it with a 660-kilogram load to return to Earth.
On 31 May, the Dragon is set to detach from the station and seek to make a safe landing in the Pacific Ocean off the coast of southern California.