Optimal Orbits for Imaging Super Massive Black Holes using Space VLBI

The diameter of the Earth constitutes a fundamental limit to current efforts of imaging supermassive black holes (SMBH). The current Event Horizon Telescope (EHT), a network of telescopes employing very long baseline interferometry (VLBI), is sufficient only for imaging M87*, due to its large mass, and SgrA*, the SMBH in the center of our galaxy. A future black hole imager requires moving from ground to space-based VLBI. Here, we investigate the benefits of augmenting the current EHT with space-based antennas that are either Earth orbiting, orbiting in cislunar space, or in a Sun-Earth Lagrange point orbit. We use evolutionary optimization algorithms to search for the trajectories in these regions that maximize diversity of antenna separations.