AST 2002 Study Guide - Midterm Guide: Oort Cloud, Inclined Orbit, Heat Transfer
Document Summary
Core- the highest-density material, consisting primarily of metals such as nickel and iron. Mantle- rocky material of moderate density mostly minerals that contain silicon, oxygen, and other elements forms a thick layer that surrounds the core. Crust- the lowest-density rock, such as granite and basalt (a common form of volcanic ro(cid:272)k(cid:895) for(cid:373)s a thi(cid:374) layer, esse(cid:374)tially represe(cid:374)ti(cid:374)g the (cid:449)orld"s outer ski(cid:374) Lithosphere- earth"s outer layer (cid:272)o(cid:374)sists of relati(cid:448)ely (cid:272)ool a(cid:374)d rigid ro(cid:272)k that esse(cid:374)tially (cid:862)floats(cid:863) o(cid:374) (cid:449)ar(cid:373)er, softer ro(cid:272)k (cid:271)e(cid:374)eath. Differentiation- the process by which gravity separates materials according to density, with high-density materials sinking and low-density materials rising; this explains why interiors are layered. Heat transfer- planetary interiors heat up through accretion, differentiation, and radioactivity and cool off through conduction, convection, and radiation. Conduction- the process by which thermal energy is transferred by direct contact from warm material to cooler material; heat flowing on the microscopic level.
