A system, method, and apparatus are disclosed for agile dedicated spacecrafts for spinning microwave imagers and sounders. In one or more embodiments, the system, method, and apparatus involve an agile, zero net-momentum, spinning space vehicle, which includes a body and an instrument package. In one or more embodiments, the instrument package is mounted directly onto the body such that the space vehicle can point the instrument package not only along the space vehicle's orbital velocity vector, but in any direction within the space vehicle's field of regard. The space vehicle's spin axis is aligned with the instrument package's scan axis. The space vehicle experiences zero net-momentum on orbit by including a counter-rotating momentum storage device. In one or more embodiments, the instrument package is a scanning microwave imaging/sounding instrument, which is utilized as an Earth climate and weather sensor.