Altern Stak was a Vulcan science officer in the 2150s.
In 2155, Stak was serving aboard the T'Jal when Romulans attempted to capture the T'Jal. He reported to Captain Vanik that the Toth had self destructed. Vanik then made a similar decision to destroy the T'Jal. (ENT novel: Beneath the Raptor's Wing)