I like the way this article starts:
There are all sorts of details to take into consideration when traveling in deep space, such as where to go, what to do, and how to get back. Since starry-eyed dreamers often don’t take into account the practical realities of putting a human into such an environment, steely-eyed engineers are left to decide the gritty details of such a mission, such as how many pairs of socks are needed.Well, it's good to see that NASA is putting serious work into how much sock drawer room is needed in space. (That sounds sarcastic, but it's not really meant to be. I would love to have my childhood doodling of spaceship designs as a real job.)
Anyway, NASA is coming up with estimates for spaceship size for long missions (this one to an asteroid.) Apart from the summary at the link, you can see the whole paper here. This is what they think a deep space mission may look like:
And here's the inside:
Those ceilings look very low and claustrophobic; but then again, I suppose in weightlessness you're not standing up often.
This also gives me the opportunity to again note that, as anyone who has ever stayed at a cheap Japanese hotel and been in one of their ultra compact bathrooms would know, the nation with the most Earth based experience for long distance space travel is clearly the Japanese. They have space underwear too. (Search my blog at the side if you are interested.)