A billion stars: The odds are long, but there’s a chance. As in, “There are a billion stars out there, so the odds are one contains what we’re looking for.”
Dirtside: Planetside. On the surface of the planet.
Drift: To let one’s spaceship continue moving in space without yet knowing its destination.
Drop a rock on it: Destroy something utterly. The term originates from warfare where asteroids are diverted to crash into a planet, or large rocks are used as ammunition for similar effect.
Go AB: To “go afterburner,” or move as fast as possible.
Go atmo: To “go atmospheric,” or enter the atmosphere of a planet.
Phreak: A derogatory term for a person with psychic abilities.
Sape: A sapient or sentient being; as opposed to a non-sapient being such as an animal. The exact definition of either is often used incorrectly, but “sape” has come to mean a being that is self-aware. Among most, this means it is not an “animal.”
Space: To force someone off a spaceship in vacuum (usually resulting in death).
To the stars: A toast to one’s ancestors, gods, or fortune.
To the last parsec...and beyond: “To the end.” Often used to express loyalty, such as “I’m with you to the last parsec, and beyond.”
Xeno: Technically, any uncatalogued species of creature or being. In more common usage, it’s a slightly derogatory term for anyone the speaker doesn’t “get” or understand.