This is great information for my hard sifi writing of a colony ship voyage.,(reply>), @Stig Yes! but then they grow up because bad things happen when they realise no one is left at the helm.,(reply>), @Stig They evenutally might get to that, but they launched in the 1950's and part of the story is the progress of science and dignity being isolated from the rest of humanity with the goal to find a home in a system that they are not sure if there will be a planet or anywhere habitable.