"ar-GRATH-a" was the pronunciation for this planet's name from the script pronunciation guide. 
According to the Star Trek: Star Charts, on page 74, Argratha was located in the Argratha system. The Argratha system was a single star system. Primary was a Class G star with a magnitude of +7, which was 1/10 as bright as Sol. Argratha was a destination on the Gamma Quadrant Bio-Survey (2369-75).