I'd imagine they are likely to be more of an issue too in the future, for longer term or more risky missions to Mars/etc. NASA try to select people who are high

I'd imagine they are likely to be more of an issue too in the future, for longer term or more risky missions to Mars/etc. NASA try to select people who are highly stable as astronauts (used to be test pilots), but when the mission only has a 25% chance of getting you home, or involves you living on Mars for a year in a garden shed, then the people who would want to volunteer are going to tend to be mentally off to begin with. I assume they've thought of this, even for lunar missions or ISS - I wonder what the protocol is? Do they bring handcuffs? Sedatives?