ROARS: Research Observatory for Atmospheric Responses to Sun-magnetosphere interactions

The Earth’s upper atmosphere is highly sensitive to solar activity and the solar wind-magnetosphere interaction. Magnetospheric current systems close through the ionosphere, where ion-neutral collisions and enhanced energetic particle precipitation can significantly modulate the spatial and temporal variability of the atmosphere's outer extent. Unlike the many isolated in-situ measurements conducted by previous space missions, distributed observations of neutral particles, plasma, and magnetic fields by a tetrahedron of micro-satellites, combined with precise tracking of satellite orbital dynamics, provide the global perspective needed to disentangle the complex transfers of energy and momentum through the tightly coupled magnetosphere-ionosphere-thermosphere system.In this presentation, we outline the ROARS F3 mission architecture. This mission seeks to obtain the first full curlometer magnetic field and energetic particle precipitation measurements in low Earth orbit (LEO), alongside concurrent measurements of the ambient plasma and neutral populations across a range of altitudes, latitudes, and longitudes. The measurement strategy is designed to resolve and characterise the energy and momentum entering the upper atmosphere, the multi-scale pathways through which these are redistributed, and the feedback mechanisms coupling back to the broader geospace environment. A comprehensive ground segment will simultaneously provide context by relating information on D- and E-region dynamics to the in-situ measurements.