If at first you don’t succeed, you might need to wait for mission control to figure out what’s wrong before you try again. As we covered last week, the initial inflation of the BEAM module went less than perfectly. The Bigelow Expandable Activity Module is important because being able to use inflatable modules as part of the ISS (or any future space station) could dramatically reduce the weight and bulk of shipping said modules into orbit. SpaceX brought BEAM to Station, collapsed for shipping, and it was installed on the aft side of the Tranquility node on April 16th. It was supposed to expand smoothly according to one of these models:
Instead, when command tried to pressurize the module, BEAM expanded by just a few inches, getting stuck in its compacted state even though its internal pressure rose sharply:
NASA shows us here what BEAM looks like while its expansion is in progress…
Now that it’s been properly inflated, the next step is to get it up to normal operating pressure. Then it will stay aboard the ISS for two years to undergo testing. Nobody is really going to live in this iteration of BEAM, even though it’s a hab module; it’s not tested well enough to trust like that yet. Instead, astronauts will routinely enter the module to take temperature readings, measure radiation levels, and make sure there are no dust bunnies building up. Only after it’s been exhaustively tested against the extreme conditions of space will it be put into service housing astronauts, experiments, or cargo.
BEAM weighs about a ton and a half, and it’s made of layers of ultra-durable fabric over a rustproof aluminum frame. To answer the looming threat of space debris puncturing the module, NASA took several precautions. First, they made its skin from many layers. From inside to outside, the skin of BEAM is made of an airtight barrier, a restraint layer providing primary structural support (think “pressure suit”), some micro-meteoroid and orbital debris (MMOD) layers, and external multi-layer insulation (MLI). Its outermost layer is made of a Teflon-coated glass fabric called BETA cloth, chosen as much for its resistance to corrosion by atmospheric oxygen as for its ballistic-grade toughness. BEAM also has a super tough MMOD shield. This is all to protect the astronauts who will eventually live and work in BEAM modules just like this, shielding them from debris and radiation while they’re in space or on other planets. And to protect the space station to which it’s attached, when BEAM is in operation, the hatches between it and the station default to closed. This means that if BEAM got hit by space junk, only BEAM would lose its air, not the whole station.
After its test period, BEAM will be robotically detached from the space station, leaving orbit to burn up in the atmosphere over about a year. This might sound crazy, based on not wanting burning space debris to fall on your head, but fear not. NASA points out that on average, there’s a spacecraft re-entry a week, which nobody ever notices because nothing ever reaches the ground. In their words: “Since the beginning of the space age in the 1950s, there has been no confirmed report of an injury resulting from re-entering space objects.”
NASA is working hard on the inflatable habitats in part because they want to do a Mars mission. On such a long trip at such a huge distance, we really need to get the most on-ground habitability for our payload buck. NASA remarks:
Anyone want to speculate on a possible future Mars collaboration between NASA, ESA, and SpaceX?