Very wide stellar binaries, with semi-major axes of hundreds of AU and larger, constitute sensitive probes of the underlying gravitational potential in which they live, having provided some of the first experimental constraints on the nature of dark matter in the Milky Way halo. As such, the detection and characterization of populations of wide binaries in nearby old dwarf galaxies could provide us with a completely new window onto the properties of dark matter on the smallest scales. We have designed a new method, geometric in its essence, for deriving the density and projected semimajor-axis distribution of a population of binary systems that does not resort to standard estimators of the two-point correlation function, and will present results of applying it to our Hubble Space Telescope survey of the Ursa Minor dwarf spheroidal galaxy. We will discuss the competing effects of the survey's depth, coverage, and angular resolution limits against those of foreground stars and background galaxies, and highlight the potential advantages that JWST and the Roman Space Telescope may offer to this specific problem.
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