ESA Directorate of Earth Observation Programmes (ESA-EOP) have seized the opportunity to support the development of small and nano-satellites to complement the EOP scientific and application-driven flagship missions. These developments include new science driven missions and constellations which enable a significant increase in temporal resolution leading to new applications. This paper presents an overview of the NewSpace paradigm, describes the overall ESA-EOP small mission strategy and provides a brief insight into some of the small satellites being developed at ESA across three programmatic lines: Scout Missions, Φ-sat Missions and the Investing in Industrial Innovation (InCubed) Programme. The paper focuses on optical missions.
We present a new mission concept, referred to as StereoSAR, with as primary aim to measure ocean surface currents at
sub-mesoscales. To improve our understanding of the role surface currents play in a large variety of geophysical
processes the mission will gather global measurements with high spatial and temporal resolution. A multi-static
configuration based on a receive-only C-band dual polarimetric Synthetic Aperture Radar system working in synergy
with Sentinel-1 is proposed. The Doppler Centroid Anomaly technique is used in order to measure Total Surface Current
Velocity vectors by combining the mono-static observation and the squinted bi-static one. Simultaneous retrieval of
Ocean Surface Wind Vectors and Ocean Swell Spectra is also performed. This paper presents an overview of the
proposed mission concept and scenario. Some issues specific to multi-static Synthetic Aperture Radar are described and
solutions offered. Finally, a preliminary performance assessment of the mission concept is included.