Starfish Prime was awesome. I wish I could have been at the meeting where someone said, "Let's set off some nukes in space, it'll be awesome!"
Is the ISS a good analog to the radiation environment that you would expect on the moon? I could be wrong but isn't the ISS close enough to Earth for the magnetosphere to most of the solar wind and other assorted charged particles whereas the moon doesn't have that benefit? It's always been somewhat fascinating to me how much extra goes into the hardware for meant to leave Earth. Reading about the effects of radiation on the systems installed on craft like Galileo and Juno so I'm curious. Is there a reason you're looking at SSDs rather than HDDs or other storage options?
It seems like accessing data on the moon would be somewhat difficult if this happens.
The ISS environment is proportionally less intense than outside of the Earth's magnetosphere. There is a measurement called "Geomagnetic cutoff rigidity". Below a certain value "rigidity cutoff energy" a particle sees the magnetic field as "rigid" meaning it can't penetrate. On the Earth, different parts of the Earth have different geomagnetic cutoff rigidities as well as different altitudes. For example, the highest geomagnetic cutoff rigidity on the surface of the Earth is 17 giga-electron volts (GeV) and at the south and north pole that number is 1 GeV. For every ten-x decrease in rigidity cutoff, there are 50x more particles of that energy.
in Low Earth Orbit (LEO), that energy is lower (lower means more particles) and there are variations. This is what the South Atlantic Anomaly is, which is an area of geomagnetic field weakness that allows more particles to lower altitudes. Its not that different from the Earth's surface. In geosynchronous orbit there is about 30% more particles than in LEO. At the Moon it is about 10-50x more particles. However, if you design for LEO conditions, that just means that you are 50x more likely to get a single event upset. That is no big deal if you have EDAC or ECC memory that can handle Single Event Upsets (SEU). Interestingly, with the advance in semiconductor tech, it is more likely to get an SEU on the Earth, than in low Earth orbit due to the fact that with the reduction in gate voltage (from 5 volts 25 years ago to 1 volt now), the energy required to upset a gate, has moved into the energy level of a muon. There are several orders of magnitude more muons than higher energy particles due to what is called "air showers" when galactic or solar cosmic rays hit the atmosphere and break up or cause fission in atmospheric particles (this is where carbon 14 comes from).
Thus your body is bathed in muons every second. When you are in an airplane you have 10x more muons. Go up in a private jet to 45,000 feet and you get another 40% more muons.
This is why you are seeing EDAC and ECC memories (DDR5 and DDR6) and fast GPU's implementing EDAC and ECC. Pay attention to the specs on high end computer memories and other parts. This helps to make space electronics better as they are now designed to accommodate radiation! For example, our Polarfire has EDAC on all the internal CPU registers and the internal FPGA has EDAC as well.
We are still looking at the issue and will take appropriate measures. For the future, one meter of regolith equals the Earth's atmosphere for protection.
Now go outside and get radiated by muons!
As for the second quote, yep, but it would be fully backed up. There are other ways of doing this on the Earth, and if we did not have crap for brains, we could solve this problem relatively inexpensively, and deal with the nuclear EMP problem at the same time.
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