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by picture 1189 days ago
Interesting! I'm designing the flight computer/electronics of a 2U cubesat for academia, and something like this might work really well for our application. We were considering borated polyethylene but the cost for that is prohibitive. This is perhaps not as efficient in terms of mass-to-protection ratio, but we have plenty more room in our mass budget instead of actual budget. I also like the idea that we may be able to mold this material around particularly sensitive elements of our system like the memory devices, to which neutrons are the biggest hazard.
3 comments

I'm pretty sure Tungsten and borated polyethylene are best at shielding against different types of radiation. Dense materials like tungsten and lead are ideal for blocking gamma rays and x-rays, while borated polyethylene is better at blocking neutrons.

Depending on your environment and the sensitivities of what you're shielding, you might need one or the other, and possibly both.

Disclaimer: I'm not a nuclear physicist. I learned this while researching for a hard-sci-fi novel I'm working on.

Academia? Cubesat projects?

Maybe get the kids to look into using Magnetorquers to get some spin on and half shield with this product .. and you now have a platform for directional gamma ray detection | mapping.

( Gamma counts coming from "over there" will decrease whenever "over there" is masked by the partial shielding )

There are other apps, but that one springs to mind.

Great idea! We do have 3 DoF magnetorquers on board, but I feel like the difference between shield on and shield off might need a very sensitive and directional detector..
It's a timing thing - Australia used a "we built it ourselves" detector with shielding that rotated about the crystal pack to find that missing mining source that hit the news last month.

The detector part (doped crystals + scintillation sensors) is fundamentally undirectional - those pesky gamma come in from any direction.

One side has to be shielded to bias the reading (use Tungsten perhaps) .. and by rotating the entire satellite the shielding direction changes - you now have a bulk data stats analysis challenge, do particular orientations align with counts (at various energy levels) rising or falling.

As alway, have a fiddle with a ground based setup first.

>As alway, have a fiddle with a ground based setup first.

now see, if we do that, then you're ruining the one chance I have of being the exact right person to go to space to fix the thing.

I feel obliged to mention coded apertures here too! https://en.m.wikipedia.org/wiki/Coded_aperture
for a cubesat saving a few bucks on machining probably isn't a good tradeoff