Sienar TF73

Sienar TF73, or just Sienar or 73, was a snow-covered planet in the Outer Rim Territories' Tharin sector that was owned by Sienar Fleet Systems. One of many numbered worlds owned by the company, 73 was home to Sienar Test Facility 73. A TIE Avenger prototype was kept there and inspected by the technician Niya. In 4 BBY, Niya helped the rebel spy Cassian Andor infiltrate the facility to steal the prototype. After prepping the TIE Avenger for a test flight, she briefed the spy, who reassured her about her sacrifice.

Andor proceeded to board the TIE Avenger and try to fly it out of the facility. Difficulty with the unfamiliar controls delayed the spy, who was forced to fight off facility security before he could break out. He was pursued by two TIE/ad v1s through 73's canyons and ultimately destroyed his pursuers with falling debris before escaping offworld.

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