Astronauts aboard the International Space Station (ISS) were well into the unpacking of the SpaceX Dragon resupply capsule on March 4, after the mission successfully overcame post-launch thruster difficulties that delayed the rendezvous and berthing by a day.

Station commander Kevin Ford, assisted by flight engineer Tom Marsburn, grappled the second SpaceX Dragon supply vessel with Canada’s 58-ft.-long robot arm on March 3 at 5:31 a.m. EST.

“It’s not where you start,” Ford told Mission Control after the capture. “It’s where you finish. You guys really finished this one on the mark.”

NASA’s Mission Control took over at that point, berthing the capsule with the U.S. segment Harmony module via remote commands at 8:56 a.m.

The station’s crew entered Dragon at 1:14 p.m. EST March 3, essentially teaming with SpaceX to regain the time lost with March 1 post-launch troubleshooting of a blockage in the helium plumbing that pressurized the oxidizer side on three of four thruster pods. By March 2, the NASA-led ISS mission management team was satisfied the SpaceX control team in Hawthorne, Calif., had overcome the blockage and successfully carried out the altitude raising maneuvers required to proceed with a rendezvous and grapple.

“Launching rockets is difficult, and while the team faced some technical challenges after Dragon separation from the launch vehicle, they called upon their thorough knowledge of their systems to successfully troubleshoot and fully recover all vehicle capabilities,” said NASA Administrator Charles Bolden, who monitored the launch and troubleshooting from Hawthorne.

The mission is the second flown by SpaceX under a $1.6 billion, 12-flight NASA Commercial Resupply Services contract awarded in late 2008.

The space agency is positioning SpaceX and Orbital Sciences Corp., which received a similar $1.9 billion resupply services contract, to restore U.S. space station cargo capabilities lost as NASA’s shuttle fleet was retired in mid-2011.

Orbital Sciences is preparing for its first launch to the station this summer, a demonstration flight that will qualify the Dulles, Va.-based company for regular resupply flights.

The Dragon CRS-2 capsule is scheduled to remain berthed to the station until March 25.

The lengthy stay is paced in part by science experiments included in a 2,700-lb. cargo delivery that will make the return journey as well.

Those investigations examine the root health of thale cress plants grown under varying oxygen levels and the solidification of lead- and tin-based liquids. In the absence of gravity, the investigations could unmask processes that reveal how plants respond to flooding and point to improved processes for producing materials from molten metals.

Over the berthing period, Dragon will be reloaded with just more than 3,000 lb. of research gear and equipment in need of refurbishment as well as protective packaging. SpaceX vessels will be positioned in the Pacific Ocean off the coast of Baja, Calif., to await the Dragon’s parachute descent for recovery.