Homeworld
The surface of the Jaridian homeworld is briefly seen in the third season, it appears to be quite rocky, with cities or possibly industrial complexes visible in the background. As the Taelons, Jaridians and Atavus (in the final season) each refer to their homeworlds, yet each are supposedly evolved from the same ancestors, it is possible that any or none of these planets could be the original homeworld of the divergent species.
Jaridia's fate is not conclusively known: in season 5, Renee Palmer states that the planet imploded, but there is no known means by which she could have found this out. The Jaridian species themselves are said to be facing death en-masse from their biological problems, but this would seem insufficient to cause such a cataclysmic event.
The position of Jaridia is not known for certain either: the planet is said to be in the Tau Ceti system. This is a real star that is relatively close to Earth (just under 12 light-years) in the consetellation Cetus. In the penultimate episode of Season 4, the character Liam Kincaid refers to the location as "a double star in the constellation Cetus". This is confusing, as though this would seem to refer to the real-world Tau Ceti, in reality, Tau Ceti is not a double star.
Given that Jaridian forces have travelled several million light-years to other galaxies, but have yet to come into close contact with Earth, this casts doubt on the idea that the Tau Ceti mentioned can be the Jaridian homeworld. Debate among some fans nevertheless remains quite heated on the subject, linking in with the debate over the FTL capabilities of the Jaridians. In the real world, Tau Ceti would be unlikely to provide an environment suitable for the formation of a stable rocky planet.
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