Wikia

Brax was an inhabited planet in the Gamma Quadrant. Its inhabitants called Q the "God of Lies", although Q claimed they did so affectionately. Vash visited Brax while in Q's company, though they were not particularly welcome. (DS9: "Q-Less")

According to the Star Trek: Star Charts (page 74), Brax was located in the Brax system. This system was a single star system. Primary was a Class G star with a magnitude of +5, which was the same brightness as Sol.