ASTR 1020 Spring 2012: Study Guide for Quiz #3

Topics you should know and understand for Quiz #3 (not necessarily a complete list)

ASSIGNED READINGS FOR THIS QUIZ: Sections 15.5 and 15.6; Chapter 18; Chapter 19; Sections 20.1 - 20.5; Sections 21.2 - 21.5.

1) DEFINITIONS: Brown dwarf, extrasolar planet, white dwarf, interstellar medium, interstellar gas, interstellar dust, emission nebulae, HII region, dark cloud, 21 cm HI line, atomic cloud, HI cloud, molecular cloud, dark cloud, globule, reflection nebula, interstellar reddening, angular momentum, angular momentum conservation, protostar, stellar evolution, main sequence turn-off, alpha particle, the triple-alpha process, electron degeneracy pressure, Pauli Exclusion Principle, Red Giant stars, horizontal branch stars, asymptotic giant branch (AGB) stars, variable stars, planetary nebulae, CNO cycle, supernovae, supernova remnant, Chandrasekhar limit, neutron degeneracy pressure.

2) MATHEMATICAL RELATIONSHIPS: the relationship between the mass of a main sequence star, its luminosity, and its lifetime; linear momentum is proportional to mass X velocity; angular momentum is proportional to mass X velocity x size.

3) OTHER THINGS YOU SHOULD KNOW: Two ways to determine the mass of a star (binary systems, the mass-luminosity relation); how extrasolar planets are found; the approximate main sequence lifetimes of OV stars, GV stars, and MV stars; how atomic, molecular, and ionized interstellar clouds are generally detected; four ways to detect interstellar dust (blocking light from objects behind a dense interstellar cloud; reddening of background stars; thermal emission in the infrared; scattering of short-wavelength light); two reasons why near-infrared observations are best for finding protostars; why protostars are relatively hot, even before nuclear fusion stars; what happens to the spin rate of an interstellar cloud when it contracts, and why; the steps in the formation of a star and what causes each step to occur; what the possible triggers of star formation are; how to determine the age of a star cluster from its H-R diagram; the steps in the triple-alpha process; the stages in the lifetime of a main sequence star; the stages in the lifetime of a high mass star; where the different chemical elements are produced.