*Communication* **CubeSat Observation of the Radiation Field of the South Atlantic Anomaly**

**Pavel Kovárˇ 1,\* and Marek Sommer 2,3**


**Abstract:** The movement of the South Atlantic Anomaly has been observed since the end of the last century by many spacecrafts equipped with various types of radiation detectors. All satellites that have observed the drift of the South Atlantic Anomaly have been exclusively large missions with heavy payload equipment. With the recent rapid progression of CubeSats, it can be expected that the routine monitoring of the South Atlantic Anomaly will be taken over by CubeSats in the future. We present one-and-a-half years of observations of the South Atlantic Anomaly radiation field measured by a CubeSat in polar orbit with an elevation of 540 km. The position is calculated by an improved centroid method that takes into account the area of the grid. The dataset consists of eight campaigns measured at different times, each with a length of 22 orbits (~2000 min). The radiation data were combined with GPS position data. We detected westward movement at 0.33◦/year and southward movement at 0.25◦/year. The position of the fluence maximum featured higher scatter than the centroid position.

**Keywords:** South Atlantic Anomaly; radiation measurement; CubeSat observation; radiation belts
