We conduct in situ small angle X-ray scattering (SAXS) experiments on D2O-nonane nanodroplets produced in a supersonic nozzle. Scattering from standard shapes like well-mixed spheres and core-shell structures does not agree with the experimental data. The 'lens-on-sphere' models suggested by molecular dynamics simulations fit the scattering data well, but the amount of D2O condensed, based on the SAXS fitting parameters, is only half of that measured by infrared absorption spectroscopy.