The Luna class is a late 24th century class of Federation Starship. The class was designed to serve as a long-term deep-space (or frontier) science vessel. Its rugged design and multiple redundancies mean it theoretically won’t need frequent visits to starbases for refit and repair. Like most Federation ships not designed specifically for combat, the Luna-class ship is lightly armed, with only six phaser arrays and three photon torpedo launchers.

It was designed specifically to accommodate a diverse crew, and several decks on the ship have atmospheres which are toxic to many humanoid races.

The USS Tethys entered service in 2370.

As the latest of the Luna-class ships off the line, several updates have been made to her systems, including an experimental bridge design that echoes that of several past Federation ships.