The detection of gravitational waves from binary neuron star merger GW170817 and electromagnetic counterparts GRB170817A and AT2017gfo kick-started the field of gravitational wave multimessenger astronomy. The optically red to near infra-red emission (‘red’ component) of AT2017gfo was readily explained as produced by the decay of newly created nuclei produced by rapid neutron capture (a kilonova). However, the ultra-violet to optically blue emission (‘blue’ component) that was dominant at early times ( (cid:46) 1.5 days) received no consensus regarding its driving physics. Among many expla-nations, two leading contenders are kilonova radiation from a lanthanide-poor ejecta component or shock interaction (cocoon emission). In this work, we simulate AT2017gfo-like light curves and perform a Bayesian analysis to study whether an ultra-violet satellite capable of rapid gravitational wave follow-up, could distinguish between physical processes driving the early ‘blue’ component. We find that a Dorado -like ultra-violet satellite, with a 50 deg 2 field of view and a limiting magnitude (AB) of 20.5 for a 10 minute exposure is able to distinguish radiation components up to at least 160 Mpc if data collection starts within 3.2 or 5.2 hours for two possible AT2017gfo-like light curve scenarios. Additional sensitivity and additional filters may allow for a longer acceptable response time. We also study the degree to which parameters can be constrained with the obtained photometry. We find that, while ultra-violet data alone constrains parameters governing the outer ejecta properties, the combination of both ground-based optical and space-based ultra-violet data allows for tight constraints for all but one parameter of the kilonova model up to 160 Mpc. These results imply that an ultra-violet mission like Dorado would provide unique insights into the early evolution of the post-merger system and its driving emission physics. In addition, this study shows that ultra-violet plus optical multi-wavelength detections provide complementary constraints, jointly covering a broader range of early ejecta properties.