PARCS meaning in General ?

The Primary Atomic Reference Clock in Space or PARCS was an atomic-clock mission scheduled to fly on the International Space Station (ISS) in 2008, but cancelled to make way for the Vision for Space Exploration. The mission, to have been funded by NASA, involved a laser-cooled caesium atomic clock, and a time-transfer system using Global Positioning System (GPS) satellites. PARCS was to fly concurrently with the Superconducting Microwave Oscillator (SUMO) a different type of clock that was to be compared against the PARCS clock to test certain theories. The objectives of the mission were to have been: