Called the Bigelow Expandable Activity Module, or BEAM, the habitat is an inflatable spheroid made of fabric that starts off folded into a shape like a flattish cone with the top cut off. It was originally launched to the International Space Station (ISS) on April 8.  

The first tests were in May. Crewmembers aboard the ISS expanded BEAM, using low pressure, and then allowed the air tanks inside the habitat to open and pressurize it to the same level as the space station — approximately one atmosphere.

Sensors inside the BEAM checked the module's temperature and how well its structure was responding to pressure. Astronauts didn't enter the BEAM until June, though, as there were extensive checks for leaks. (They found none.) NASA astronaut Jeff Williams was the first to enter the BEAM, and he added extra sensors to monitor the atmosphere inside it.