A constellation of nanosatellites for geodesy, space weather and radio occultation experiment: An Australian example from Spire Global CubeSats

The recent paradigm shift in space technology (miniaturized sensors, smaller spacecrafts, affordable launches) opens accessibility to space at unprecedented levels. Many ground-breakings ways of utilizing space-borne platforms will be sought after in order to enable space-based solutions to many national and global problems in the Earth system change. One of the important issues for the Australian space and radio science and defence is to monitor and forecast space weather events. Space weather influences performance, efficiency and reliability of technological infrastructure. Irregularities in ionospheric plasma density, particularly at lower latitudes, may produce adversary effects on navigation, communications and surveillance systems in Australia. Spire Global has been pioneering small satellite technology for maritime, aviation and weather forecasting applications. With their successful launch and operation of a constellation of 3U CubeSats equipped with dual frequency GNSS receivers as one of the payloads, Spire Global has demonstrated its leadership in the space-borne Earth Observation industry. Unprecedentedly massive sampling of GNSS measurements over the globe for improved weather forecasting became feasible. In this paper, we will present the results of analyzing sample dual frequency GNSS tracking data from the CubeSat constellation provided by Spire Global, with the focus on retrieving and validating Total Electron Content (TEC) over the Australian continent and precise kinematic trajectory for gravity and geodesy experiment. We will share what we have learned from analysing Spire Global data to demonstrate the feasibility of using a small, low-powered, dual frequency GNSS receivers for Earth Observation.