Because NASA has plans to launch a substantial number of Earth-observing spacecraft over the next 15 years, it would be more efficient to operate these spacecraft in groups, as opposed to single entities. Enhanced formation flying technology will enable a large number of spacecraft to be managed with a minimum of ground support. The result will be a group of spacecraft with the ability to detect navigation errors and cooperatively agree on the appropriate maneuver to maintain their desired positions and orientations. Formation flying technology enables many small, inexpensive spacecraft to fly in formation and gather concurrent science data in a "virtual platform." This concept lowers total mission risk, increases science data collection, and adds considerable flexibility to future Earth and space science missions.

In particular, the science output from the Aqua mission will be enhanced through coordinated flying with several other satellites that will be obtaining complimentary data sets. These other satellites, in order after Aqua in the lead, are CALIPSO, CloudSat, Parasol, and Aura. Because this sequence starts with Aqua and ends with Aura, it has been termed the "A-Train."