T'Mir was a Vulcan explorer during Earth's 20th century. She was T'Pol's second foremother (great-grandmother) and T'Les's foremother (grandmother). In 1957, the vessel that T'Mir was serving on was investigating the first artificial satellite launched by Humans, then a pre-warp civilization, Sputnik I. Her vessel crash landed on Earth in the small town of Carbon Creek, Pennsylvania, in the United States of America. She took command when the captain of the vessel was killed in the crash. After running out of food, she and Mestral, one of her two remaining crewmates, walked to the town of Carbon Creek, stole Human clothes, and then entered a local tavern. Needing money, Mestral played a game of pool and won enough money to buy food.