High-inclination NEAs as meteor stream parent bodies

Abstract

<p>Recent meteor radar surveys have uncovered a subpopulation of meteoroids with high orbital inclination and at a=1 au, in the form of a grouping of radiants within the southern toroidal source of sporadic meteors (Brown et al, Icarus, 2010;  Pokorny et al, Icarus, 2014). Many of these showers are so far not detected in optical surveys (Jenniskens et al, PSS, 2018; Bruzzone et al, PSS, 2020), implying a meteoroid population deficient in large particles, such as might result from the gradual, size-sorting action of P-R drag.</p> <p>Here we consider that the source of this population is one or more Near-Earth Asteroids (NEAs) in similar, high inclination orbits. We test this hypothesis by numerical integration of test particles ejected from a selection of suitable NEAs and evolving under the influence of radiation forces. We pay particular attention to the role of dynamical resonances near Earth's orbit as well as the Kozai mechanism in confining the meteoroids, countering the dispersive action of drag forces and gravitational scattering.</p> <p>We will report on the outcome of our simulation runs at the meeting.</p>