El-Adrel system
The El-Adrel system was an uninhabited planetary system that was located near to Tamarian space. The fourth planet, El-Adrel IV, was the homeworld of a non-sentient species. 

In 2368, a Tamarian deep space cruiser commanded by Captain Dathon chose this system to attempt communication with the Federation. He chose the fourth planet because the opportunity of working together with a Starfleet captain in defeating a member of this species offered a parallel with a story in their mythology. The  was sent to answer their signal. ()

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ja:エル・アドレル星系
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Star systems