ASTRO 142 Study Guide - Final Guide: Red Giant, Nuclear Fusion, Cno Cycle
Document Summary
Cosmological principle: universe looks the same no matter your position. The early universe was hotter and denser then it cooled and expanded. Hotter objects emit more light at all frequencies per unit area. Hotter objects emit photons with a higher average energy. Universe"s expansion has red shifted thermal radiation from that time to. Redshift: z=d / can be thought of as v/c. Undetected form of mass that emits little or no light. Repulsive force that causes the expansion of the universe to accelerate. Reactions between 2 or more types of objects. Rate of reaction depends on available energy and density of reactants. Proton and neutron fuse to form a deuterium nucleus. Particle annihilation: early universe full of particles/radiation b/c high temp. Critical density=density of matter required for a coasting universe. Flat universe : mass + energy density = critical. Closed universe : mass + energy density > critical. Open universe : mass + energy density < critical.
