NASA

NASA

NASA

NASA

NASA

Bigelow Aerospace

NASA TV

SpaceX

NASA

NASA

In April, astronauts attached an expandable room to the International Space Station, which they successfully inflated at the end of May. This week, NASA astronaut Jeff Williams entered the Bigelow Aerospace expandable module and said everything was fine. He subsequently installed some sensors to monitor air pressure, temperature, and other variables, as well as other hardware.

Finally, on Wednesday, Williams removed his tools from the module and closed the hatch. Astronauts will not reenter the 13-foot-long module now until August, when they will perform more checks of the equipment.

Why wait so long? Because as important as it was to demonstrate the module could be expanded, it is more important still to prove its durability over the two-year experiment. Engineers with Bigelow have said the expandable’s kevlar-like weave should be at least as protective as the station’s aluminum hull when it comes to tiny orbital debris. The company also says that with this material, the interior of the module should prove a quieter location than the notoriously noisy station interior. NASA is also interested in how the non-metallic shell of the module limits radiation exposure.

This experiment, for which NASA has a $17.8 million contract with Bigelow, will allow the space agency to fully test out a concept it has been interested in since the 1990s. The inflatable module was initially proposed as a crew quarters module for the International Space Station, but the inflatable program got canceled as the station went through a series of budget cuts. Bigelow subsequently licensed the technology and brought it forward to maturity.

Expandables have the potential to revolutionize spaceflight because they solve one of the biggest problems by providing large habitat areas for a relatively low mass and size within a rocket's payload fairing. Inflatable modules could be used both in space as well as eventually on the surface of the Moon or Mars. But first we need to see how the test module works out on the station and how well it holds up during the next couple of years.

Listing image by NASA