A planet in a system threatened by the nova of its star, where the Vians test the empath Gem in a hidden laboratory.
Minara II is the site of a Federation research station monitoring its sun, which is about to go nova. In The Empath, the Enterprise arrives to evacuate the two scientists stationed there, only to find the station abandoned.
Kirk, Spock and McCoy are transported to an underground laboratory where the Vians are conducting tests on the empath Gem. The outcome decides whether her people will be saved from the coming nova.