Astronauts aboard the International Space Station have inflated an experimental fabric module that could help house crews for long stays in space.

Bigelow Aerospace designed and built the Expandable Activity Module (BEAM), which would be the first inflatable habitat tested with astronauts in space and potentially provides a less expensive and safer option for housing crews, according to a NASA statement.

Bigelow Aerospace, a Las Vegas-based prviate corporation, flew two unmanned prototypes before this. Lightweight inflatables are easier and less costly to launch than metal modules, and could provide better protection from radiation.

Inflatable modules could be critical to getting crews to Mars. The trip would require many months in space, and an inflatable module would likely be needed to make it feasible.

Astronaut Jeff Williams began inflating BEAM recently while working inside the ISS. He opened a valve to release air into the module, and reported short popping sounds, which may have been stitches in the module rupturing, which they are supposed to do during expansion.

Astronauts will wait a week before entering the module to install radiation and temperature sensors.

“Expandable habitats are designed to take up less room on a spacecraft, but provide greater volume for living and working in space, once expanded,” the statement reads. “This first test of an expandable module will allow investigators to gauge how well the habitat performs and, specifically, how well it protects against solar radiation, space debris and the temperature extremes of space. The module is an example of NASA’s increased commitment to partnering with industry to enable the growth of the commercial use of space.

“The International Space Station serves as the world’s leading laboratory for conducting cutting-edge microgravity research, and is the primary platform for technology development and testing in space to enable human and robotic exploration of destinations beyond low-Earth orbit, including asteroids and Mars.”