Mavala IV

From Memory Alpha, the free Star Trek reference.

Mavala IV is the fourth planet in the Mavala system, where Dr. Noonien Soong and Juliana O'Donnell went to get secretly married in 2328. Their wedding was witnessed by a Corvallen and Klingon traders.

The planetary government was overthrown sometime after 2328, which led to many documents being lost including the Soongs' wedding certificate. (TNG: "Inheritance")