Cargo ship wraps up smooth space station rendezvous
Back in action after a spectacular failure last year, an Orbital ATK Cygnus cargo ship pulled up to within 30 feet of the International Space Station early Wednesday and then stood by while astronaut Kjell Lindgren, operating the lab's robot arm, locked onto a grapple fixture to wrap up a two-and-a-half-day rendezvous.
With the supply ship firmly in hand, ground controllers at the Johnson Space Center were clear to begin executing complex robot arm commands to slowly pull the spacecraft in for berthing at the Earth-facing port of the central Unity module.
"Cygnus capture is complete," Lindgren radioed Houston after the 6:19 a.m. grapple.
"Outstanding! There is much rejoicing on the ground," replied Canadian astronaut David Saint-Jacques in mission control. "Thank you guys, well done."
"Thank you, and our thanks and congratulations on a phenomenal team effort in delivering the Cygnus vehicle and its precious cargo to the International Space Station," Lindgren said.
"It went flawlessly," Saint-Jacques agreed, "textbook perfect."
For Lindgren, the Cygnus capture marked a final major event before work to complete preparations for undocking and return to Earth Friday, along with Soyuz TMA-17M commander Oleg Kononenko and flight engineer Kimiya Yui, to close out a 141-day stay aboard the outpost.
Undocking is targeted for 4:49 a.m. EST (GMT-5) Friday with landing on the steppe of Kazakhstan expected around 8:12 a.m. The crew's replacements -- Soyuz TMA-19M commander Yuri Malenchenko, flight engineer Tim Kopra and British astronaut Tim Peake -- are scheduled for launch from the Baikonur Cosmodrome next Tuesday.
While Lindgren, Kononenko and Yui continue departure preparations, station commander Scott Kelly plans to open the forward hatch of the Cygnus spacecraft early Thursday to clear the way for unloading.
The Cygnus is packed with nearly 7,400 pounds of equipment and supplies, including nearly 200 pounds of computer gear, 2,600 pounds of food, clothing and other crew supplies, 500 pounds of spacewalking gear, 2,220 pounds of station hardware and spare parts and about 1,865 pounds of science gear.
The cargo ship also is carrying Christmas gifts and other personal items for the six crew members who will be on board at the end of the month: Malenchenko, Kopra, Peake, Kelly, Mikhail Kornienko and Sergey Volkov.
Kelly and Kornienko are in the home stretch of a nearly yearlong mission. They plan to return to Earth with Volkov on March 1. Their replacements are scheduled for launch March 18.
The Cygnus spacecraft was launched Sunday from the Cape Canaveral Air Force Station atop a United Launch Alliance Atlas 5 rocket. It was the first launch of a Cygnus since an Orbital Antares booster exploded seconds after liftoff Oct. 28, 2014.
Two subsequent failures of a Russian Progress supply ship and a SpaceX Dragon freighter earlier this year cut into the station's on-board reserves, reducing margins from about six months to less than four in some cases.
But the arrival of the Cygnus, two successful Progress flights in July and October, a Japanese HTV cargo vehicle in August and another Progress later this month are easing those concerns, with additional cargo flights planned early next year.
