SpaceX's Dragon supply ship completed a laser-guided rendezvous with the International Space Station early Sunday, transporting a trial expandable enclosure for attachment to the complex later this month for tests to confirm the inflatable design's suitability for future space habitats.
The module will increase to about four times its launch volume next month, starting a two-year demo campaign to check the lightweight habitat's flexibility to adjust to the harsh conditions of space.
The automated Dragon cargo capsule reached the space station from below Sunday, beating its rocket jets to direct the spacecraft to a point about 30 feet (10 meters) from the complex, close enough for the robotic arm to reach out and hold the SpaceX supply freighter.
Astronauts will go in the Dragon spacecraft Monday to start unpacking nearly 3,800 pounds (1,723 kilograms) of supplies, provisions and experiments inside the capsule's pressurized compartment.
The lynchpin of Dragon's 3.5-ton cargo load is the Bigelow Expandable Activity Module, or BEAM, a trailblazer for future inflatable habitats that could form commercial space stations, carry astronauts to deep space destinations, and even shelter explorers on the surface of Mars.
Engineers have subjected BEAM to stricter requirements because it will be momentarily occupied by astronauts. Designers also attuned the deployment mechanism to expand in length and diameter when inflated.
NASA is remunerating Bigelow Aerospace based in North Las Vegas, $17.8 million for the demo, which will last at least two years.
At the end of demo, the module will be separated and released with the space station's robotic arm. It will, in due course, burn up during re-entry into Earth's atmosphere.