ASTR 121 Study Guide - Comprehensive Final Exam Guide - Sun, Galaxy, Milky Way
20 Nov 2018
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Astr121 lecture 1 review of astr120: logistics, office is at psc 1112, office hours: m 10 11 am, w 2 3 pm, phone #: 301-405-8786, e-mail: dcr@astro. umd. edu, t. a. Iron is a dead end for fusion since nuclear reactions involving iron do not release energy. Astr121 lecture 6 pulsars and neutron stars: upcoming due dates, skim ch. It had a period of exactly 1. 337301 seconds. This implies that there is some sort of invisible substance of gravitational mass outside of the galaxy: mapping the milky way, to map the milky way, we need luminous, un-obscured sources. Astr121 lecture 14 other galaxies: learning goals, classify a galaxy as spiral, elliptical, or irregular based on morphology and further estimate the subtype of spiral (barred, tightness of arms, etc. A particular subtype of cepheid star is called an rr lyrae variable: cepheid variable stars with longer periods have greater luminosities, henrietta leavitt is credited with this discovery.
