Earth as a Planet (Astronomy)

Recall cards studying Earth as one of the terrestrial planets. Its bulk properties: diameter, mass, record-high density, and escape velocity. Its layered interior built by differentiation: the basaltic oceanic and granitic continental crust, the deep mantle, the iron core, and the magnetic field and magnetosphere the liquid core produces. Its restless crust: igneous, sedimentary, and metamorphic rock, roughly a dozen tectonic plates driven by mantle convection, seafloor spreading, subduction, faults, continental drift, and hot spots. Its atmosphere: the nitrogen-oxygen-argon mix, sea-level pressure, the troposphere, stratosphere, and ionosphere, the ozone layer, and weather versus climate. The coevolution of life and air: the oldest rocks, stromatolites, the rise of oxygen, and present-day carbon dioxide and the greenhouse effect. And the cosmic impacts that have shaped Earth, from Tunguska and Chelyabinsk to Meteor Crater and the Chicxulub impact that ended the age of the dinosaurs.