Tidal disruption of NEAs - a case of Příbram meteorite

Abstract

This work studies the dynamical evolution of a possible meteor stream along the orbit of the Příbram meteorite, which originated in the tidal disruption of the putative rubble-pile-like parent body during a close approach to the Earth. We assumed the disruption at the time when the ascending or descending node of the parent orbit was close to the Earth's orbit. In the last 5000 yr, the Příbram orbit has crossed the Earth orbit twice. It happened about 4200 and 3300 yr ago. In both cases, we modelled the release of particles from the simplified model of rotating asteroid, and traced their individual orbital evolution to the current date. It takes several hundred years to spread released meteoroids along the entire orbit of the parent body. Even today, the stream would be relatively narrow. Considering a model parent body with physical parameters of the asteroid Itokawa, the complete disintegration of the object produced 3.8 × 1011 meteoroid particles with diameter ≥1cm. The meteor activity observed from the Earth is revealed and justification of follow-up observation during suggested activity of the shower in the first two weeks of April is discussed. The Earth's tidal forces would disintegrate a fraction of the New Earth Asteroid (NEA) population into smaller objects. We evaluate the upper limit of the mass of disintegrated asteroids within the mean NEA lifetime and the contribution of disrupted matter to the size distribution of the NEA. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.