T'Khasi at Surak's Passing was a map of the 40 Eridani star system created by the Vulcan artist T'Sari in the 4th century.
The map was an artistic representation of the Nevasa system, as it was then named by its Vulcan inhabitants. It showed the primary star Nevasa A (40 Eridani A), its orbiting planets and moons Ket-Cheleb, T'Khasi (Vulcan), T'Khut and T'Rukhemai, and the other two orbiting stars Nevasa B (40 Eridani B) and Nevasa C (40 Eridani C). It was labelled in Ceremonial Golic Vulcan script.
In the late 24th century, T'Khasi at Surak's Passing was held in the Antiqities Division of Memory Alpha's Central Archives.
In the year 2387, the map—along with nine others from the United Federation of Planets' allies, neighbours and enemies—was published to represent a multifaceted view of known space. The ancient Vulcan language was translated into Galactic Standard by Memory Alpha archivist, Leigh Burke. (ST reference: Stellar Cartography: The Starfleet Reference Library)