* Capsule to re-enter atmosphere and burn up on Wednesday
* NASA now has second U.S.-based supply line to station
* Firm preparing to fly next cargo ship in December
By Irene Klotz
CAPE CANAVERAL, Fla., Oct 22 (Reuters) - Virginia-basedOrbital Sciences Corp completed a successful testmission at the International Space Station on Tuesday, clearingthe firm to begin regular cargo runs for NASA under a $1.9billion contract.
Using the space station's robotic arm, astronauts aboard thestation plucked the Orbital Sciences' Cygnus capsule from itsdocking port and released the unmanned capsule into space as thetwo sailed high over the Atlantic Ocean.
The capsule was launched on Sept. 18 aboard an OrbitalSciences' Antares rocket from a new commercial spaceport onWallops Island, Virginia.
Cygnus arrived at the station 11 days later. Docking wasdelayed a week due to a spacecraft communications glitch and thehigher priority arrival of new station crew members aboard aRussian Soyuz capsule.
"This test flight went pretty much without any hiccups atall," NASA mission commentator Josh Byerly said during a NASATelevision broadcast of Cygnus' departure.
The capsule is scheduled to make two braking maneuvers onWednesday to lose altitude so it can be tugged back into Earth'satmosphere by the planet's gravity and burn up.
Cygnus, which carried about 1,300 pounds (590 kg) of cargoto the station, was loaded up with trash and items no longerneeded aboard the station before its release.
Orbital Sciences is the second of two U.S. firms hired byNASA to fly cargo to the space station, a $100 billion projectof 15 nations, following the retirement of the space shuttles in2011.
Rival Space Exploration Technologies, or SpaceX, a privatelyowned California company, began work for NASA about 18 monthsbefore Orbital Sciences. It has already made a test flight andtwo cargo runs to the station, a permanently staffed researchcomplex that flies about 250 miles (about 400 km) above Earth.
SpaceX, which is owned and operated by billionaireentrepreneur Elon Musk, has a $1.6 billion NASA contract for 12station resupply missions, as well as a backlog of more than 40other Falcon rocket flights for commercial satellite companiesand non-U.S. government agencies.
"We are delighted to now have two American companies able toresupply the station," NASA administrator Charles Bolden said ina statement.
"Congratulations to the teams at Orbital Sciences and NASAwho worked hard to make this demonstration mission to theInternational Space Station an overwhelming success," he said.
Like SpaceX, Orbital Sciences also hopes to sell its rocketsto customers beyond NASA.
"With two really good launches under our belt, things arepicking up in terms of customer interest," Orbital SciencesChairman and Chief Executive David Thompson said during aconference call with investment analysts last week.
The company debuted its medium-lift Antares rocket during atest flight on April 21. Its next mission, scheduled forDecember, is the first of eight cargo runs to the station undera $1.9 billion contract with NASA.
- Orbital Sciences