Miniature energetic electrostatic analyzer designed for CubeSat missions

The use of miniature satellites, known as CubeSats, has rapidly grown in recent years, from low Earth orbit applications such as remote sensing to the first interplanetary mission to Mars in 2018. As CubeSats continue to advance, low-power miniaturized instruments to expand their capabilities has become paramount.

Maldonado et al. have developed an instrument called the Energetic Electrostatic Analyzer (EESA), which provides in situ measurements of ion or electron energy, density, temperature and subsequent spacecraft charge. EESA fits within a standard 10 cm×10 cm ×10 cm miniature satellite unit weighing less than 1.33 kilograms.

EESA could be used for building more durable satellites to withstand the harsh ionospheric environment, analyzing the plumes of rocket plasma thrusters to determine their effects on the surrounding environment, and improving overall space weather forecasting.

The researchers built EESA using a new laminated electrode design, which consists of a stack of miniaturized parallel-plate electrostatic energy analyzers. The sensor head is composed of three conducting electrode layers, with patterns of holes and slots etched in stainless steel plates to create thousands of analyzer elements. Each of these elements has an entrance aperture, cavity and exit aperture. Varying the voltage across the electrodes allows the sensor to measure charged particles distributions with a range of energies from 0 to 5 keV.

“The laminated design is key to the miniaturization of the instrument,” author Carlos Alex Maldonado said. “This comes at the cost of angular response but can be accounted for by incorporating several heads in the same device.”

In addition to a primary payload for CubeSat missions, the EESA can be used as a secondary payload on larger satellites.

Source: “A laminated energetic electrostatic analyzer for 0-5 keV charged particles,” by C. A. Maldonado, Z. Eyler, B. Pierce, L. Matson, P. Neal, H. K. Richards, R. L. Balthazor, J. Harley, and M. G. McHarg, Review of Scientific Instruments (2019). The article can be accessed at https://doi.org/10.1063/1.5123395 .