Origin an physical structure of small solar system bodies

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The small bodies of the solar system (asteroids, comets) are relics formed during the birth of our solar system. They contain primitive material which has not experienced substantial processing. Their physical structure, chemistry and dynamical evolution offer a unique window into the early solar system providing strong constraints for solar system formation models. The small debris liberated from these bodies, called meteoroids, occasionally collides with the Earth. Accretion of meteoric material is believed responsible for delivery of much of the Earth's water inventory and meteors contributed substantially, through shock synthesis during their atmospheric passage, to the organic compounds available on the early Earth, thereby playing a role in the emergence of early life. While we are all made of stardust, the most immediate pre-biotic process leading to life may well be associated with meteors. This proposal's goal is to perform a broad survey of the small bodies of the solar system using their debris (meteoroids) as a proxy for parent body structure. In particular, I intend to study the ablation behaviour of meteoroids in the Earth's atmosphere (meteors) from specific meteor showers to better understand particular parent bodies. These measurements will be performed using two existing facilities: an automated radar (the Canadian Meteor Orbit Radar) and two automated optical meteor stations (the Canadian Automated Meteor Observatory) both novel facilities for meteor observation, without peer globally. Using these observations it is possible to infer properties of the original meteoroid, such as its material strength, bulk density, chemical composition and physical structure. Knowing the orbits of each recorded meteoroid, we are then able to link these measurements back to the originating parent body or class of parent bodies. From this information we gain a better understanding of where each meteoroid comes from, what processes may have operated on its immediate parent as well as the overall ecology of near-Earth space. By understanding the makeup of meteoroids and how they have interacted with the Earth we are looking back in time to the earliest stages of the Earth's history when bombardment from above formed our world.