Ventures
Ventures represent talents beyond the deployment specialization of a character. This embodies their training and experience in other aspects of their lives. At certain deployment ranks, your deployment gives you the Venture feature. You can take each venture only once, unless the venture's description says otherwise.
You must meet any prerequisite specified in a venture to take that venture. If you ever lose a venture's prerequisite, you can't use that venture again until you regain the prerequisite. For example, the Spacecasting venture requires you to be able to cast force or tech powers. If your character loses the ability to do so, you can't benefit from the Spacecasting venture until you regain the ability to cast force or tech powers.
Ventures, and this book in general, are designed and written in such a way that they have minimal impact on the ground game. All ventures are intended to only be usable while deployed aboard a ship, even if they don't explicitly say it.