Astrea Tendi was an Orion scientist who lived during the 23rd century. She was the great-grandmother of Starfleet officer D'Vana Tendi, and like her descendant, she used the title Mistress of the Winter Constellations.
In 2259, Astrea was serving aboard the science vessel D'Var when it encountered a time portal on Krulmuth-B. The portal had been used in 2381, sending Ensigns Brad Boimler and Beckett Mariner back in time. While Boimler had previously believed that the portal was discovered by the USS Enterprise, D'Vana Tendi had insisted it had been found by an Orion science vessel, and that her great-grandmother was part of the crew. Boimler's experience in the past proved D'Vana right, as Enterprise captain Christopher Pike gave credit for the discovery to the Orion scientists. (SNW: "Those Old Scientists")
This character was only mentioned in dialogue.