MEGASIM: Distribution and Detection of Earth Trojan Asteroids

Using the MEGASIM, we present spatial distributions of Earth Trojan Asteroids and assess the detectability of the population in current and next-generation ground-based astronomical surveys. Our high-fidelity Earth Trojan Asteroid (ETA) distribution maps show never-before-seen high-resolution spatial features that evolve over timescales up to 1 Gyr. The simulation was synchronized to two surveys, 1) the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) and 2) the Zwicky Transient Facility (ZTF) public and partnership survey. Upper limits were calculated for the ETA population for ZTF (with assumed null detection) and LSST's cadence simulations. For LSST, a null detection is within three sigma of the simulation results out to H=19 for the twilight survey and H=20 for the baseline survey. Due to the Yarkovsky Effect, no ETAs are stable on billion year timescales are likely to be detected. ETAs large enough to remain stable on billion year timescales are very rare relative to the rest of the ETA population. A null detection in LSST will restrict that population to tens of objects larger than 100 meters. The null detection by ZTF to date has already done so.