SUMMARY

Radiation shielding research covers a wide range of technologies. One such area is the study of novel materials and their effects on reducing the space radiation dose to astronauts. This is especially significant as the space age transitions to long term space flights and inhabiting the lunar surface or the Martian surface; missions that may not be able to avoid solar energetic particles, such was the case for the Apollo 16 crew.

Recently, the National Aeronautics and Space Agency (NASA) has been interested in studying a novel material known as boron nitride nanotubes (BNNTs). In radiation physics, boron, has long been known to be an effective radiation shield against neutrons, due to its high neutron absorption cross section, and against charged particles, due to its relatively high charge to mass ratio. BNNTs are also attractive because of their mechanical properties, which suggest they may be able to replace aluminum alloys as structural components for spacecraft, while also providing radiation shielding. Further, the nanotubes can be woven into fabric, suggesting some implementation into spacesuits, which will reduce radiation dose during extravehicular activities (EVAs) by astronauts. BNNTs are also a great candidate for hydrogen loading. These materials can be hydrogenated which further improves neutron shielding and charged particle shielding as hydrogen has the highest charge to mass ratio.

The following analyses have studied the radiation shielding advantages of BNNTs compared to aluminum alloys. The effects of galactic cosmic radiation (GCR), solar particle events (SPEs), and secondary neutrons are considered. Further, various Hydrogen loading into BNNTs are studied. Granted, the following analyses are obtained through nuclear physics simulations and lack experimental data, the results give valuable insights into BNNT radiation shields and allude to some experimental setups for further studies and validation.