The "Hunt" for Micrometeorites Parent Bodies.

The application of the accretion formula to the Earth-Moon system does not require the identification of the parent bodies of micrometeorites (i.e., asteroids or comets). However, this identification is necessary to better extrapolate this formula to other terrestrial planets, such as Mars. One would also like to understand how the invariant composition of micrometeorites constrains the nature of their parent bodies. We report on a few arguments that have not been thoroughly explored yet, and which run against the conventional view that most micrometeorites originate from the collisions and/or erosion of asteroids. The only remaining alternative is that they dominantly originate from comets. [ABSTRACT FROM AUTHOR]