In April, astronauts attached an expandable chamber to the International Space Station, which they successfully inflated in late May. This week, NASA astronaut Jeff Williams entered the Bigelow Aerospace Expandable Module and said everything was fine. He then installed some sensors to monitor barometric pressure, temperature and other variables, as well as other hardware.
Finally, on Wednesday, Williams took his tools out of the module and closed the hatch. Astronauts will now not re-enter the 4-meter module until August, when they will conduct more checks on the equipment.
Why wait so long? Because as important as it was to show that the module could be expanded, it is even more important to prove its durability over the two-year experiment. Bigelow engineers have said the expandable’s Kevlar-like fabric should be at least as protective as the station’s aluminum hull when it comes to small orbital debris. The company also says that with this material, the module interior should prove to be a quieter location than the notoriously noisy station interior. NASA is also interested in how the module’s non-metallic shell limits radiation exposure.
This experiment, for which NASA has a $17.8 million contract with Bigelow, will allow the space agency to fully test a concept it has been interested in since the 1990s. The inflatable module had initially been proposed as a crew quarters module for the International Space Station, but the inflatable program was canceled when the station went through a series of budget cuts. Bigelow then licensed the technology and advanced it to maturity.
Expandables have the potential to revolutionize space travel as they solve one of the biggest problems of providing large habitats for a relatively low mass and size within a rocket’s fairing. Inflatable modules can be used both in space and eventually on the surface of the Moon or Mars. But first, we need to see how the test module at the station plays out and how well it holds up over the next few years.
List image by NASA