Tidal disruption of NEAs - a case of P\v{r}\'ibram

TL;DR

This study models the tidal disruption of a near-Earth asteroid, linking it to the Příbram meteorite stream, and estimates the resulting meteoroid production and its contribution to NEA population dynamics.

Contribution

It provides a detailed dynamical simulation of asteroid disruption and meteoroid stream formation, connecting it to observed meteor activity and NEA population effects.

Findings

Disrupted asteroid could produce 3.8×10^{11} meteoroids ≥ 1cm.

Stream remains narrow for several hundred years after disruption.

Earth's tidal forces can disintegrate NEAs, affecting their size distribution.

Abstract

This work studies the dynamical evolution of a possible meteor stream along the orbit of the P\v{r}\'{i}bram 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 years, the P\v{r}\'{i}bram orbit has crossed the Earth orbit twice. It happened about 4200 years and 3300 years ago. In both cases, we modeled 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$\times10^{11}$ meteoroid particles with diameter $\geq$ 1\,cm. 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 NEA population into smaller objects. We evaluate the upper limit of mass of disintegrated asteroids within the mean NEA lifetime and the contribution of disrupted matter to the size distribution of the NEA.