A civilian passenger vessel commanded by Jon Daily that was due to carry the Karidian Company of Players from Planet Q in 2266, until Kirk asked it to pass them by.
The Astral Queen is mentioned in The Conscience of the King and not seen. It was a commercial passenger ship under Captain Jon Daily, an acquaintance of James Kirk.
The touring Karidian Company of Players, led by the actor Anton Karidian, was booked to leave Planet Q on it for their next engagement on Benecia. Kirk suspected Karidian of being Kodos, the former governor of Tarsus IV who had ordered the deaths of four thousand colonists, and he wanted time to make sure.
He quietly asked Daily to skip the stop. With the players stranded, Karidian's daughter Lenore came to Kirk for passage, as he had intended, and the company travelled on the Enterprise. Daily later reported the favour to Starfleet as a matter of routine.