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AskPhysics: How close to the speed of light could you get before most starlight is blue shifted to ionizing radiation? (lemmy.ca)

submitted 10 months ago by troyunrau@lemmy.ca to c/physics@mander.xyz

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[–] HeckGazer@programming.dev 3 points 10 months ago* (last edited 10 months ago) (1 children)

A couple non-quantitative thoughts on this:

Space is big and empty. In order to have significant amounts of radiation energy hitting you you'd have to be going quite close to stars thanks to the cube energy drop-off.
Space probes do have this kind of shielding on their chips! They also use multiple independent identical processors that vote on results as it's unlikely for a high energy particle to scramble a majority of the chips in an identical way. This is also why space tech tends to use old manufacturing nodes that have huge (by earth bound comparison) transistors.

[–] troyunrau@lemmy.ca 1 points 10 months ago* (last edited 10 months ago)

Good points.

I wonder what the dose would look like to a square metre, framed in human reference terms. Better or worse than medical imaging. That would require figuring out photon flux, above 750nm. But there is also relativistic cross section changes happening, so does that affect the flux?

I'm reminded of a first year physics prof that suggested we figure out how fast we'd need to go to fit through the head of a needle (in a vacuum).

The redundant computing this is a fantastic invention. I'm aware that SpaceX is using off-the-shelf computers for this instead of the longstanding tradition to use only "rad hardened hardware", preferring to rely on multiple redundancy for weight and cost savings. Without knowing the flux at 0.95c though, it'd be hard to estimate how well the strategy would work :)