CASPER - Combined analysis of space weather effects on near-Earth satellites

Accompanying with the rapid technological progress in the last decades space weather effects can directly be perceptible in people’s everyday life. During high solar activity phases, the number of solar eruptions like flares and coronal mass ejections (CMEs) increases. These solar phenomena have the capability to trigger geomagnetic storms, which may disrupt and damage satellites in space as well as technical infrastructure on Earth. In February 2022 two sequentially occurring CMEs triggered a geomagnetic storm that resulted in the loss of 40 Starlink. A recent ESA study estimated that the potential socio-economic impact in Europe today from a single extreme space weather event could be about €15 billion. With a view to the rising solar cycle it is mandatory to monitor and at best accurately forecast extreme space weather conditions. In the predecessor FFG project SWEETS the applicants have developed the forecasting tool SODA, to predict the expected satellite orbit decay triggered by CMEs. The results were very encouraging, which is why the service SODA will become part of ESA’s Space Safety Program (ESA-SSA) in the next portal release in 2023. Nevertheless, to confirm the achieved recognition within the scientific community it is essential to further develop and improve the existing service as well as acquire further knowledge in this research topic. In the project CASPER, we aim to further develop SODA based on an interdisciplinary exploration of interplanetary observations and measurements of the ionosphere-thermosphere. In terms of thermosphere density modelling, it is envisaged to improve the existing solutions by means of a sophisticated modelling of the spacecraft re-radiation and the integration of satellite self-shading routines. In addition, SODA will be extended to predict the impact of CMEs for different altitude layers. Moreover, solar eruptions have the capability to change the amount of ionization of the atmosphere due to high energy particles from the Sun. Since, these incidences are especially critical for GNSS navigation signals, it is the aim to carry out a combined analysis of the ionosphere-thermosphere. For the examination of the ionosphere, we apply the in-house developed GNSS “Raw Observation Approach”. This approach has impressively demonstrated its advantages in the latest IGS repro3 campaign and its application in this field of research represents a novelty. Regarding the examination of CMEs, the most recent events in February 2022 have shown that the structure of a CME can be decisive for the severity of the impact. Thus, the focus during the examination is on (1) the interactions between sequentially occurring CMEs and (2) the analysis of CME substructures which have a different behavior in propagation through interplanetary space and impact on the Earth’s near environment. With that in mind, the project CASPER is intended to make a significant contribution to more safety and security in space in the future.