Inflatable habitats are the next big thing in space. As we reported back in March, aerospace engineers at NASA are set to inflate a module made out of kevlar-like material that will serve as another room on the International Space Station. The room is called BEAM, otherwise known as The Bigelow Expandable Activity Module. It cost around $17.8 million to build and is being inflated, tomorrow, the 26th of May. The success of the mission could see more inflatable habitats being designed for spacecraft.
The engineers behind the project took to social media side Reddit to answer some of the public's burning questions ahead of the expansion which will be streamed live on NASA's website at 5:30 a.m. ET. Here are some of the highlights of what was asked to the engineers and what their answers were:
Q: How do you handle radiation? I image that an expandable structure must be initially compact, making it difficult to have good radiation shielding and be safe for human usage.
A: Radiation protection is indeed critical for astronauts on the Space Station and eventually traveling to Mars. As a technology demonstrator, BEAM will be fully instrumented with a variety of sensors by the Space Station crew after deployment and ingress, including thermal, debris impact, and radiation sensors. In addition, there are already sensors on the aft bulkhead that will measure dynamics loads during deployment this Thursday. Data from the sensors inside BEAM will be downloads by engineers on the ground throughout the 2-year mission on the Space Station. This data will be invaluable for the viability and design of future expandable habitats. Radiation can behave differently when passing through multiple fabric layers vs. metallic shells. It remains to be seen how BEAM's radiation protection will compare to standard metallic modules, but that is a big part of the reason for doing this tech demo, paving the way for the use of expandable structures in future exploration missions
- Steve Munday, NASA BEAM Deputy Manager
Q: For deep space missions, how do you envision your inflatable habitats protecting astronauts from radiation and how, if at all, will the gas(es) used to inflate the structure vary based on application? Are there any plans on eventually incorporating self-healing polymers in your future designs so as to make your structures more robust in the unlikely event of a minor puncture?
A: Inflatables have protection in terms of MMOD (Micrometeorite and orbital debris) and thermal protection ad has a robust MMOD and thermal protection design. BEAM demonstration will provide us data on radiation protection. The gas used to inflate the structure if it is used for habitats has to be 21% Oxygen breathing air. Self-healing polymers are very advanced materials with low TRL (Technology readiness level) but will be used for future designs of inflatables. If successful, they can provide a huge benefit
- Rajib Dasgupta, NASA BEAM Project Manager
The benefits of expandables? Dasgupta explains that they can be used for deep space habitats on Mars as well. He says they can transport them in a packed state and then expand them on Mars, which is a huge benefit, so that little houses can be erected on the surface of Mars. The data of the expansion happening on the 26th will give the engineers enough data to further establish their Martian intensions.
Q: Has any thought gone into how to safely decommission the BEAM module once it has reached its end-of-life? Are there any special considerations to take as compared to the standard modules?
A: The end of mission plan is to jettison BEAM from below the Space Station using the robotic arm. BEAM will naturally drift away from the Space Station and re-enter the earth's atmosphere about a year later. NASA engineers have analyzed this reentry and determined it will pose an extremely low risk to people on the ground. Remember that most of BEAM is made of fabric materials that will burn up quickly during reentry. The metallic parts of BEAM (for example, the two bulkheads on either end) are made of aluminum which should also burn up during entry. Even in a worst case scenario in which most or all of these bulkheads make it all the way to the ground, there is an extremely low risk of falling near anyone according to conservative computer model analysis.
The rest of the Space Station also will reenter the earth's atmosphere after the end of its usable lifetime, but it will be a controlled, guided entry, meaning it will be targeted to enter above an ocean, far from populated areas. BEAM has no propulsion or guidance capability, but still poses an extremely low risk to us on the ground.
- Steve Munday, NASA BEAM Deputy Manager
The engineers explain that BEAM will utilize 8 air tanks that will inflate the balloon to its full expansion, however, some air from the Space Station is used for the initial phase of expansion happening tomorrow. The two big takeaways from the Q&A session was the possible uses for these sorts of inflatable habitats on other planets and how that would work. Not surprising if considering that the engineers are a collection of NASA and Bigelow engineers that have been assisted by SpaceX engineers. It is set to be a very interesting time in their histories as they continue to build up to an eventual Mars mission.