Sikaris was an inhabited planet in the Delta Quadrant and was the homeworld of the Sikarians. Its system had a single sun. It had a mantle of tetrahedral quartz twenty kilometers thick, which served as an amplifier for the Sikarians' spatial trajector technology.
Given that the distance between Sikaris and Alastria is "two and a half billion times the distance Sikaris is from its sun", Sikaris would be 160 million kilometers from its sun.
According to the Star Trek: Star Charts (pp. 78, 83), the Voyager visited this planet on stardate 48642. Sikaris was located in a binary star system (contradicting the episode). Both the primary and the secondary were K-class stars.
Sikaris was the third planet in the Sikaris system. This M-class planet was governed by the Sikaris Canon from the capital city of L'hur. The dominant species was the humanoid Sikarians. In 2378, there were 620.5 million Sikarians living on the planet. Sikarians have been warp-capable since antiquity.