Engineers have determined SpaceX's Dragon cargo resupply spacecraft can launch March 30 without repairs after an analysis showed contaminants inside the ship's unpressurized trunk pose no additional risk to optical communications and imaging payloads heading for the International Space Station, according to a statement released Friday.

The Dragon spacecraft is attached to the Falcon 9 booster inside SpaceX's hangar at Cape Canaveral. Photo credit: SpaceX
 
SpaceX said it is targeting liftoff of the Dragon spacecraft on a Falcon 9 rocket at 10:50 p.m. EDT on March 30 (0250 GMT on March 31) from Cape Canaveral's Complex 40 launch pad.

Officials delayed launch from March 16 after engineers raised concerns that petroleum stains discovered on thermal blankets could contaminate sensitive components on a high-definition imaging camera and an optical communications experiment mounted inside the Dragon spacecraft's trunk.

"After careful review and analysis, engineering teams representing both the ISS and SpaceX have determined Dragon is ready to fly 'as-is.' All parties agree that the particular constituents observed in Dragon's trunk are in line with the previously defined environments levels and do not impose additional risk to the payloads," SpaceX said in a statement.

The Dragon spacecraft will deliver 2.4 tons of equipment to the space station. The robotic spaceship is scheduled to reach the outpost April 1 if launch occurs March 30.

Most of the payloads are packed inside the Dragon's pressurized cabin, including 1,576 pounds of science and research equipment, 1,049 pounds of crew supplies, 449 pounds of vehicle hardware, and 271 pounds of spacewalk tools.

The space station crew will unload the gear inside the Dragon spacecraft's internal module.

Two larger payload packages inside the Dragon's unpressurized section will be removed and stowed on the space station using the outpost's Canadian robotic arm and Dextre robot.

Artist's concept of the OPALS laser communications payload on the International Space Station. Photo credit: NASA
 
NASA's Optical Payload for Lasercomm Science, or OPALS, will demonstrate a laser communications link between the space station and a ground antenna in Wrightwood, Calif. OPALS will test uplink and downlink capability through an optical beacon as the space station passes over the Wrightwood antenna, with each communications session expected to last about 100 seconds.

Optical communications systems offer higher data transfer rates than achievable through conventional radio systems. OPALS is expected to run its experiments over a 90-day period while attached to a logistics carrier on the space station's truss.

"OPALS represents a tangible stepping stone for laser communications, and the International Space Station is a great platform for an experiment like this," said Michael Kokorowski, OPALS project manager at NASA's Jet Propulsion Laboratory. "Future operational laser communication systems will have the ability to transmit more data from spacecraft down to the ground than they currently do, mitigating a significant bottleneck for scientific investigations and commercial ventures."

The High-Definition Earth Viewing camera suite will also launch inside the Dragon spacecraft and will be hosted on a platform on the exterior of the European Space Agency's Columbus laboratory module.

Photo of the HDEV payload prepared for launch at the Kennedy Space Center. Photo credit: NASA
 
Developed by engineers at the Johnson Space Center in Houston, the HDEV system includes four commercially available high-definition video cameras that will stream live video of Earth for online viewing, according to a NASA fact sheet.

The experiment will help NASA determine what cameras work best in the harsh environment of space.

The optical communications and high-definition video systems are the first large unpressurized NASA experiments assigned for delivery to the space station by SpaceX.

The Dragon mission is the third operational resupply flight to the space station contracted to SpaceX under a $1.6 billion deal covering 12 launches through 2016.

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