Earth Magnetic Fields Observation Using LAPAN-A3 Small Satellite

LAPAN-A3, an Indonesian small satellite launched in 2016, carried a magnetometer sensor as one of its payloads to measure the Earth’s magnetic field for a scientific mission. As it is not the satellite’s primary mission, there are some limitations due to the lack of onboard instruments. First, only one fluxgate magnetometer onboard without a scalar magnetometer, which is commonly found in other satellites. Second, the satellite does not have a boom for the magnetometer. With such limitations, the mission becomes a unique problem compared to other satellites. This research studies the residual measurement and the factors that may degrade the measurements. The data that was used is all the 2019–2020 measurements. These resulted in 94.3% of scalar components having residuals less than 300 nT and 91%, 93.1%, and 92.9% of the North, East, and Down components, respectively, with residuals less than 500 nT. It is revealed that three factors affect the measurement, the availability of the satellite’s attitude data, the satellite activity, and system time inaccuracy. While the magnetorquer activity is the most significant, communication to the ground also affects the measurements. It is also revealed that the system time inaccuracy can increase residuals in vector or scalar components more than the unavailability of attitude data.