In 1957 a Vulcan ship observing Earth crashed near Carbon Creek, Pennsylvania, and its stranded crew lived among humans, a century before official first contact.
The Vulcan crew was studying Earth from orbit after the launch of Sputnik when a malfunction forced the ship down in Pennsylvania. The captain was killed, and T'Mir, Mestral and Stron hid their identity and lived for months among the townspeople, renting rooms from a tavern owner.
Mestral used a phaser to help rescue trapped miners, and T'Mir sold the idea for a hook-and-loop fastener to pay for her landlady's son's college education. When a rescue ship came, Mestral chose to remain on Earth. T'Pol told the story in 2152 as the tale of her great-grandmother.