MIT’s MicroMAS is a small, low-cost CubeSat containing a miniaturized microwave scanner that paves the way for future constellations of similar satellites, gathering more detailed, more frequent images of severe weather that impacts people on Earth.
Microwave radiometers measure temperature, water vapor, and cloud ice in the atmosphere, since oxygen and water vapor naturally emit signals in the microwave portion of the electromagnetic spectrum. These signals are measured at different heights and are used to make 3D images of hurricanes, tropical storms and thunderstorms.
The Microsized Microwave Atmospheric Satellite (MicroMAS) provides thermal images of hurricanes, tropical storms, and severe weather:
- is a low-cost, low-power, highly miniaturized 118 GHz microwave radiometer.
- has a unique dual-spinning CubeSat design (2U bus, 1U microwave radiometer)
- offers unprecedented temporal and spatial coverage of storm systems
- improves modeling and forecasting of severe weather impacts
MicroMAS) is a dual-spinning 3U CubeSat equipped with a passive microwave spectrometer that operates nine channels near the 118.75-GHz oxygen absorption line. The focus of this first NanoRacks-MicroMAS mission is to observe convective thunderstorms, tropical cyclones, and hurricanes from a near-equatorial orbit. The payload housed in the “lower” 1U of the dual-spinning 3U CubeSat is mechanically rotated approximately once per second as the spacecraft orbits the Earth, resulting in a cross-track scanned beam with a full width at half-maximum (FWHM) beam width of 2.5 degrees and an approximately 20 km diameter footprint at nadir (directly below) incidence from a nominal altitude of 400 km.
Radiometric calibration is carried out using observations of cold space, the Earth’s limb (edge of the planet), and an internal noise diode that is weakly coupled through the radio frequency (RF) front-end electronics. In addition to the dual-spinning CubeSat, a key technology development is the ultra-compact intermediate frequency processor module for channelization, detection, and analog to digital conversion.
The payload antenna system and RF front-end electronics are highly integrated, miniaturized, and optimized for low-power operation. To support the spinning radiometer payload, the structures subsystem incorporates a brushless direct current (DC) zero-cogging motor, an optical encoder and disk, a slip ring, and a motor controller.
High-resolution, fast imaging of Earth’s atmosphere gives weather forecasters better information about hurricanes, tropical storms and other severe weather. Improved observations aid weather forecasting and disaster-response preparations, as well as scientific research on the evolution of storm systems. NanoRacks-MicroMAS supports the development of more advanced nanosatellite control systems, which are used for a wide range of Earth-observing and communications applications.