• 3 Posts
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Joined 5 months ago
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Cake day: December 14th, 2024

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  • Lifetime dose limit, fine. 100mSv/year is the lowest associated with a significant increase in cancers. 2Sv is severe radiation poisoning, possibly even fatal. Of course we’re talking over maybe a 18month period, probably more like 2 to 3 years.

    Ok, so let’s say upper side of the full dose is 2Sv over 3 years. That’s 666 mSv/year, so right now that doesn’t look great. But it gets worse as you break it down. ~55mSv/ month. ~2mSv/day. That’s a lot. Like ~500 dental X-rays a day. Obviously distributed throughout the body.

    5% of people exposed to 1Sv lifetime dose will die of a fatal cancer.

    I can’t find a lot on what 666mSv/year would do to you, but from everything I gather, it would definitely shorten your lifespan. I certainly wouldn’t volunteer for it.


  • Not to mention, there is still a scale of size, time and resource contraint. We can’t send humans to Mars with all the tools they don’t know they need yet, just like we can’t send the rovers with all the tools we can imagine.

    For humans to benefit from rapid discovery on Mars, they’d need to be able to produce those tools, chemicals, power, etc.

    It would take decades to set up anything useful for a longer term mission on Mars, and it again becomes a numbers game. The longer period of time you have to account for, the wider the room for error. I don’t know many people who would be comfortable traveling through space knowing that they may not see Earth again either.



  • I’m of the opinion we can’t safely travel to mars. Not in our lifetimes.

    The earth has a nice magnetic field that protects us from background ionizing charged particles, and an atmosphere that catches most other radiation (X-ray, gamma).

    The length of time it would take with modern rockets to get to mars exposes the crew to extreme radiation. They could survive it, but radiation over time kills you with cancer, if you survive any acute effects.

    We could maybe make superconducting magnets strong enough to create a field to reduce the charged particles, but then you have to keep them powered, and still deal with the uncharged background radiation (mostly gamma/X-rays). You could create a giant cylinder of lead around the crew capsule, but that would take an extraordinary amount of time to build in orbit.

    Not to mention once you are on mars, you have to maintain those protections too - the Mars atmosphere is too thin to be very helpful and it does not have a a magnetic core.

    There has been a notable lack of progress in that realm, and it will likely remain the reason we don’t see a human to mars program.












  • It’s a Prusa MK4, so I’ll get it upgraded to the Core One to get it enclosed, and construct a vent.

    Based on what I’m reading, the glass transition isn’t the issue, it’s the plastic itself. PLA is brittle, and taking supports off creates an incredible mess. I also use ASA, and while it seems to be less brittle, there’s still quite a mess. (Thankfully, ASA doesn’t breakdown to release the styrene until it hits 400C, and the extrusion temp is 260C. That means the accumulation of the microplastic doesn’t include the carcinogenic aspect, just the ones listed and suspected of micro plastics in general).

    I used to use an SLA printer since I like making minis, but the resin started irritating the shit out of me, was insanely difficult to clean, and apparently the UV reactant is carcinogenic. I stopped using that entirely 4+ years ago (maybe used it for 6 months irregularly). I want another, but not without a much better workspace and proper ventilation. Except it, as well, results in a resin copolymer that I would find extremely likely to cause the same micro plastic hazard.