A Space Traveller's Career Maximum

At one point nine years, a space traveller would receive zero point five severts s v. Severts is the common measure an effective radiation dose. You are not a nastional any more if you're at one s v. But i wonder though, steven, i mean, what go di goand woul go to a hundredyo. I know they didn't keep going to see. At what point, wot, how big would you have to get? How thright? Bas wel talk about how thick this shielding is before you actually start to reduce the ability of those dorter particles to propagate all the way through the shielding. And wod at lorgan, but