Trialas IV
Trialas IV was the fourth planet in the Trialas system. This was a Class M planet near the Borderland.

History
When Doctor Arik Soong  stole Augment embryos from Cold Station 12 in the 2130s, he fled to Trialas IV, where he raised the Augments until he was captured by Earth forces ten years later.

 
The Augments raised themselves until May 2154, when Malik led them in commandeering a . They all left the planet, except for Udar, who was deemed inferior by the others. A few days later,  visited the planet to understand more about Soong and the Augments. When the ship left, Udar went with it. ()

Background information 
The name of this planet was not specified in the episodes (the script of "Borderland" simply referred to it as "a Class-M planet"). However, the planet's name was given in the final draft script of "Cold Station 12". In the same script, Soong's compound on the planet's surface, in 2154, was described thus; "It's a large, single-story structure that resembles a futuristic Quonset hut, nestled in a small canyon with exotic alien flora now starting to overrun the compound."

The  identified this planet as Trialas IV.

According to Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), the Trialas system was located in the Beta Quadrant. 

The scene depicting the Enterprise in orbit of Trialas IV was a reuse of Qo'noS from .

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Trialas 04