MoonLITE: the Lunar InTerferometry Explorer

The MoonLITE (Lunar InTerferometry Explorer) project is an NASA Astrophysics Pioneers proposal to develop, build, fly, and operate the first separated-aperture optical interferometer in space, delivering faint, sub-milliarcsecond science results. MoonLITE will leverage the Pioneers opportunity to fly as a hosted payload aboard NASA’s Commercial Lunar Payload Services (CLPS), to deliver an optical interferometer to the lunar surface. This would enabling unprecedented discovery power, combining high spatial resolution from optical interferometry with deep sensitivity from the stability of the lunar surface. Following a CLPS landing, the CLPS rover will deploy the pre-loaded MoonLITE outboard optical element 100 meters from the lander, establishing a interferometric observatory with a single deployment. MoonLITE combines a 110 microarcsecond limiting spatial resolution with enough sensitivity to observe targets fainter than 17th magnitude in the visible. The capabilities of MoonLITE open a unique discovery space that includes direct size measurements of the smallest, coolest stars and substellar brown dwarfs; searches for close-in stellar companions orbiting exoplanet-hosting stars that could confound our understanding and characterization of the frequency of earth-like planets; direct size measurements of young stellar objects and characterization of the terrestrial planet forming regions of these young stars; measurements of the inner regions and binary fraction of active galactic nuclei; and probing the very nature of spacetime foam itself. A portion of the observing time of this revolutionary capability will be also made available to the broader community via a guest observer program. MoonLITE takes advantage of the CLPS opportunity to place an interferometer in space, on a stable platform - the lunar surface - and delivers an unprecedented combination of sensitivity and angular resolution, at the remarkably affordable cost point of Pioneers.