NEOMOD: A New Orbital Distribution Model for Near Earth Objects

Near Earth Objects (NEOs) are a transient population of small bodies with orbits near or in the terrestrial planet region. They represent a mid-stage in the dynamical cycle of asteroids and comets, which starts with their removal from the respective source regions -- the main belt and trans-Neptunian scattered disk -- and ends as bodies impact planets, disintegrate near the Sun, or are ejected from the Solar System. Here we develop a new orbital model of NEOs by numerically integrating asteroid orbits from main belt sources and calibrating the results on observations of the Catalina Sky Survey. The results imply a size-dependent sampling of the main belt with the \(\nu_6\) and 3:1 resonances producing \(\simeq 30\)\% of NEOs with absolute magnitudes \(H = 15\) and \(\simeq 80\)\% of NEOs with \(H = 25\). Hence, the large and small NEOs have different orbital distributions. The inferred flux of \(H