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PHY 111, Spring, 2006
Week 11
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Main Objectives
 | You should know
 | why mass and luminosity are related |
| the two primary factors that determine the properties of a star |
| what stars on the main sequence have in common |
| what determines how long a star remains on the main sequence |
| how elements heavier than iron are formed |
| how astronomers are looking for black holes |
| what the Chadrasekhar limit is |
| what a protostar is and what the criteria is for deciding when a protostar becomes a
star |
| how to determine the age of a star cluster |
| what a planetary nebula is and what causes it |
| what interstellar reddening is and what causes it |
| that hot, luminous stars of spectral type O and B often occur in clusters in association
with interstellar gas clouds and what significance this has in our ideas of the origin of
stars |
| what angular momentum is and how it relates to star formation |
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| You should be able to explain
| why there are no stars with masses less than 1/12 that of the Sun and none greater than
100 solar masses |
| what is meant by the term "helium flash" |
| why a star will eventually run out of nuclear energy |
| how a white dwarf is formed |
| what causes a supernova |
| why the most massive stars have the shortest lifetimes |
| what causes a star to become a red giant |
| how emission nebula, absorption nebula, and reflection nebula are produced |
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| You should be able to describe:
| the composition of the interstellar medium |
| the process through which a star is formed |
| the three ways in which a star can lose mass |
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| You should be able to describe neutron stars, pulsars, and black holes. |
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| Tuesday |
Discussion of interstellar medium and how stars are formed. Outside
of class: Read Chapter 14 Sections 3-8 and Ch. 15 Sec 1-3. Complete Chapter 13
review questions 1, 5, 9, 11 13, 17 and question to ponder 3 to be turned in on Thursday. |
| Thursday |
Lecture on how stars change during their lifetimes. Outside
of class: Read Chapter 15 sections 4, 5, 6, and 8. Complete Ch. 14 recall
questions 1, 3, 7, 9, 13, 19, 21, 25, and 27 as well as Ch. 15 recall questions 1, 3, and
15 to be turned in next Tuesday. Begin your review for the next exam. |
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