Also totally sucks for accessibility. Some communities strictly enforce having alt text for posts.

Transcript:

souldagger

im sorry i just found out that all steel made post-ww2 has like subtly higher levels of radioactivity..... bc the nuclear bombs increased the background radiation in the air slightly all across the world and so atmospheric air used in the production of steel contaminates it.... and it's completely negligible in everyday life and not at all dangerous (really, truly do not worry about it) but apparently it also means that whenever we need Special No Radiation Steel (like for scientific/medical equipment, ex. geiger counters or xray machines) we have to use scavenged steel made before ww2. and apparently shipwrecks are a great source of such steel. so a lot of such equipment is made from recycled shipwreck metal. what the fuck. what the fuck

for anyone who like me was worried we will one day run out of shipwreck steel: thankfully the background radiation levels in the atmosphere have been dropping ever since nuclear testing was moved underground, so this will become less and less of an issue with time, and now for another radioactive metal from shipwrecks fan fact:

apparently lead is really good for radiation shielding, which is why it's important to many physics experiments, especially those concerned with studying dark matter and rare particles. unfortunately, lead is also inherently A Little Bit Radioactive (unrelated to nuclear bombs, it's just a feature of the metal), but the radioactive element decays over time, so the older the lead, the less radioactive, and hence better for Physics Stuff. which is why ancient Roman lead is Ideal for this, so a lot of ancient bars of lead from Roman shipwrecks - tons of cargo that would've ended up as weapons or coins and stuff, if it didn't sink to the bottom of the sea - are sold to physicists. it's like a whole "preservation of cultural heritage vs revolutionary scientific research" thing. like a whole fucking feud btwn the archaeologists and physicists