The Nature and Origin of Meteorites

abundance accretion Acta addition ages amount Anders Angra dos Reis appear assumed asteroids atmosphere aubrites calculated carbon chondrules classes common composition condensation contain cooling cosmic ray Cosmochim crater crust decay depth determined Earth Planet effects elements equation estimates et al eucrites example exposure ages fall figure formation formed fragments gases Geochim Geophys given greater groups heat higher howardites impact important initial iron meteorites isotope known less Lett lower major mass material measurements mechanism melting metal metamorphism methods million minerals Nature nebula nuclide observed occurred orbits ordinary chondrites origin parent bodies pattern possible present pressure probably produced range ratio reflect represent require resemble rocks seems shock silicates similar solar specimen stones stony meteorites structure studies suggested surface tektites temperatures terrestrial track usually values volatile Wasson