Meteorites are invaluable tool in our attempts to understand the origin of the Solar System and the formation of planets. Most meteorites originate from the asteroid belt between the orbits of Mars and Jupiter– a region of the Solar System where gravitational perturbations by Jupiter prevented accretion of bodies much larger than a few hundred km in diameter. The levels of heating or alteration experienced by these small planetisemals is often much less than that experienced by the terrestrial planets. Such limited asteroidal processing means that there remains an abundant repository of information in materials that were formed in the solar accretion disk, or even pre-date the formation of the Solar System in the form of interstellar grains. Most tantalisingly, some meteorite types contain abundant complex organic material and offer exceptional insight into pre-biotic chemistry.
The formation of the asteroids is a complex interplay between accretion and disruption due to impact. While this can make interpreting the information contained within meteorites challenging, the plus side is that we have many different types of materials, sampling both interior and exterior portions from a large number of different bodies.