CSSWE, like most satellites, is a collection of subsystems. In order to organize the subsystems, the requirements flow-down is defined throughout the mission development, bolstered by mass, power, data, and link budgets, as well as a risk analysis. A 3U CubeSat is defined as a small volume (10cm x 10cm x 30cm), small mass (≤4kg), and completely autonomous (i.e. power, communications) satellite. The CSSWE architecture reflects the “keep it simple” method of satellite development; the system design was simplified to meet requirements rather than designed to “push the envelope.” Two microcontrollers (MCUs) are present in the system, and two subsystems (attitude control system & thermal) are almost entirely passive. The command & data handling (C&DH) board and communication (COMM) radio are commercial off the shelf (COTS) purchases in an effort to minimize risk.