CAPE CANAVERAL, FL (USATODAY.com)- A private capsule carrying cargo from the International Space Station ison its way back to Earth after being released Tuesdayfrom the station's 57-foot robotic arm.
Flight controllers in NASA's Mission Control Center in Houston grappled the unmanned SpaceX Dragon capsule with the arm at 4:10 a.m. ET and moved it away from the Earth-facing port of the station's U.S. Harmony module.
U.S. astronaut Thomas Marshburn and Chris Hadfield of the Canadian Space Agency let the spacecraft fly free at 6:56 a.m.from a work station in the complex's Cupola module, a seven-window observation deck on the U.S. side of the outpost.
Once released, thrusters on the spacecraft ignite to push the Dragon away from the outpost. Three thruster firings move the carrier out of the station's immediate vicinity.
A retrograde thruster firing will take place at 11:42 a.m. EDT, slowing the spacecraft enough to drop it onto a supersonic plunge back through the atmosphere. A parachute-assisted splashdown about 250 miles off the coast of Baja California is scheduled at 12:34 p.m. EDT.
The Dragon spacecraft, which launched March 1 from here atop a Falcon 9 rocket and arrived at the space station March 3 after a day's delay because of thruster problems, is hauling back 2,668 pounds of experiment equipment and science samples. SpaceX Dragon capsules are the only spacecraft capable of returning large amounts of cargo to Earth now that the U.S. shuttle fleet is retired. Other station resupply ships are filled with trash and deliberately incinerated during atmospheric reentry.
SpaceX, founded in 2002 by PayPal and Tesla Motors entrepreneur Elon Musk, is the only private company ever to return a spacecraft from low-earth orbit. It has had two previous successful trips to the space station and back, in May and October last year.
SpaceX vessels and personnel were deployed to the splashdown area Sunday. The return had been planned for Monday, but rough seas prompted a one-day delay.
The SpaceX recovery fleet includes a 185-foot barge equipped with cranes to lift the spacecraft onto the vessel. A smaller crew boat carries engineers and a dive team. Two rigid-hull inflatable boats round out the fleet.
The Dragon should be returned Wednesday to the Port of Los Angeles.
On Thursday, U.S. astronaut Chris Cassidy and Russian cosmonauts Pavel Vinogradov and Alexander Misurkin are scheduled to blast off from Baikonur Cosmodrome in Kazakhstan for their journey to the International Space Station.
Their six-hour flight to the outpost will mark the first same-day launch-to-docking for a Russian Soyuz spacecraft. Two-day trips have been the norm since the first expedition crew opened the orbiting laboratory complex in November 2000.
The three-man crew already aboard also includes Russian cosmonaut Roman Romanenko.