Regula Class: D Type: Planetoid

Satellites: Regula I

Location: Mutara sector Affiliation: United Federation of Planets

Regula was a remoteplanetoidin the Mutara sector within Federation space, a Class D body according to the planetary classification. Regula was orbited by the research outpost.

According to Captain Spock of the USS Enterprise, Regula was "essentially a great rock in space."

It was later revealed that the research team developing the Genesis Device, led by Doctors Carol Marcus and David Marcus, had constructed a giant cave inside the planetoid, filled with various plantlife and water. According to Carol Marcus, it had taken the Starfleet Corps of Engineers ten months to dig out the underground structure, while the matrix used to terraform the cave only needed a day to take shape. (TOS movie & Duty, Honor, Redemption novelization: The Wrath of Khan)