BEAM expansion
A series of photos tracks the expansion of the BEAM module on the ISS May 28. Credit: NASA

WASHINGTON — An expandable module on the International Space Station finally deployed to its full size May 28 after a day’s worth of work, overcoming earlier problems with the experimental module.

NASA announced that the Bigelow Expandable Activity Module (BEAM) had expanded to its full size shortly after 4 p.m. Eastern, more than seven hours after ground controllers, working with ISS astronaut Jeff Williams, started the deployment process. A short time later, air tanks inside BEAM released air to bring the module’s pressure up to the same level as the rest of the station.

BEAM reached its full size after a gradual, and at times tedious, process of manually adding air to the module. NASA took a slow approach, sometimes asking Williams to open an air valve for as little as one second before waiting for an extended period to see how the additional air affected the expansion.

Later in the day, as engineers became more comfortable with the expansion process, they instructed Williams to add more air, and to do so more frequently. That sped up the expansion process, stretching the module’s length by 170 centimeters from its stowed configuration, while increasing its diameter to 322 centimeters.

This was the second attempt to deploy BEAM. NASA halted an initial effort on May 26 after a few hours of work where the module did not expand as much as expected. NASA officials said May 27 they believed friction between the folded fabric layers of the module was stronger than expected, causing the deployment to go slowly.

NASA expects astronauts to enter BEAM in about a week, after conducting leak checks and other tests. Astronauts will outfit BEAM’s interior with sensors, but will largely leave the module undisturbed. BEAM will remain on the station at least two years to test how expandable modules could be used for both deep space habitats as well as commercial space stations.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...