Nearly 2.5 tons of NASA science investigations and cargo are on the way to the International Space Station (ISS) aboard SpaceX's Dragon spacecraft. The spacecraft launched atop a Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida at 3:25 p.m. EDT Friday, April 18.

The mission is the company's third cargo delivery flight to the station through a $1.6 billion NASA Commercial Resupply Services contract. Dragon's cargo will support more than 150 experiments to be conducted by the crews of ISS Expeditions 39 and 40.

"SpaceX is delivering important research experiments and cargo to the space station," said William Gerstenmaier, NASA associate administrator for Human Exploration and Operations. "The diversity and number of new experiments is phenomenal. The investigations aboard Dragon will help us improve our understanding of how humans adapt to living in space for long periods of time and help us develop technologies that will enable deep space exploration."

The scientific payloads on Dragon include investigations into efficient plant growth in space, human immune system function in microgravity, Earth observation, and a demonstration of laser optics communication. Also being delivered is a set of high-tech legs for Robonaut 2, which will provide the humanoid robot torso already aboard the orbiting laboratory the mobility it needs to help with regular and repetitive tasks inside the space station.

Dragon also will deliver a second set of investigations sponsored by the Center for the Advancement of Science in Space (CASIS), which manages the portion of the space station that is designated a U.S. National Laboratory. The investigations include research into plant biology and protein crystal growth, a field of study experts believe may lead to beneficial advancements in drug development through protein mapping.

On its way to the ISS, SpaceX's Falcon rocket jettisoned five small research satellites known as CubeSats that will perform a variety of technology demonstrations. The small satellites are part of NASA's Educational Launch of Nanosatellite, or ElaNa, mission, and involved more than 120 students in their design, development and construction. One of the satellites, PhoneSat 2.5, is the third in a series of CubeSat missions designed to use commercially available smartphone technology as part of a low-cost development effort to provide basic spacecraft capabilities. Another of the small satellites, SporeSat, is designed to help scientists study the mechanisms by which plant cells sense gravity -- valuable research in the larger effort to grow plants in space.

Dragon will be grappled at 7:14 a.m. on Sunday, April 20, by Expedition 39 Commander Koichi Wakata of the Japan Aerospace Exploration Agency, using the space station's robotic arm to take hold of the spacecraft. NASA's Rick Mastracchio will support Wakata in a backup position. Dragon is scheduled to depart the space station May 18 for a splashdown in the Pacific Ocean, west of Baja California, bringing from the space station nearly 3,500 pounds of science, hardware, crew supplies and spacewalk tools.

The ISS is a convergence of science, technology and human innovation that demonstrates new technologies and makes research breakthroughs not possible on Earth. The space station has been continuously occupied since November 2000. In that time, it has been visited by more than 200 people and a variety of international and commercial spacecraft. The space station remains the springboard to NASA's next great leap in exploration, including future missions to an asteroid and Mars.

For more information about SpaceX's third cargo resupply mission and the International Space Station, visit:

http://www.nasa.gov/station

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