Spatially resolved accretion-ejection in compact binaries with GRAVITY

The GRAVITY instrument at the Very Large Telescope Interferometer has led to the first spatially resolved observations of X-ray binaries at scales comparable to the binary orbit, providing unprecedented spatial information on their accretion-ejection mechanisms. In particular, observations of the hypercritical accretor SS433 have revealed a variety of spatial structures at the heart of this exotic microquasar, including bipolar outflows, super-Keplerian equatorial outflows and extended baryonic jets photoionised by collimated ultraviolet radiation.