1 of s Like s of Other Stellar The Lives And Deaths of s a Sun-like s More 10/29/2009 My Office Hours: Tuesday 3:30 PM - 4:30 PM 206 Keen Building
2 Test 2: 11/05/2009 of s Like s of Other a Sun-like s More Now is a good time to start reviewing. Use the study guides! Look again at homeworks and miniquizzes! 1 Test is mandatory 2 Covers chapters Consists of 35 questions
3 Outline of s Like s of Other a Sun-like s More 1 of s Like s of Other 2 3 a Sun-like 4 5 s More 6
4 Outline of s Like s of Other a Sun-like s More 1 of s Like s of Other 2 3 a Sun-like 4 5 s More 6
5 Stage 1: An Interstellar Cloud of s Like s of Other Interstellar cloud starts to contract, probably triggered by shock or pressure wave from nearby star. As it contracts, the cloud fragments into smaller pieces. a Sun-like s More
6 of s Like s of Other a Sun-like s More Stage 2 Stages 2 and 3: A Contracting Cloud Fragment Individual cloud fragments begin to collapse. Once the density is high enough, there is no further fragmentation. Stage 3 The interior of the fragment has begun heating, and is about 10,000 K.
7 of s Like s of Other a Sun-like s More The Orion Nebula is thought to contain interstellar clouds in the process of condensing, as well as protostars.
8 of s Like s of Other a Sun-like s More The Orion Nebula is thought to contain interstellar clouds in the process of condensing, as well as protostars.
9 Stage 4: A Protostar of s Like s of Other a Sun-like s More Some 100,000 years after fragment formed, it reaches stage 4: Nuclear reactions have not yet begun. The core of the cloud is now a protostar, and makes its first appearance on the H-R diagram.
10 of s Like s of Other a Sun-like s More
11 of s Like s of Other Planetary formation has begun, but the protostar is still not in equilibrium All heating comes from gravitational collapse. a Sun-like s More
12 Stage 5: Protostellar of s Like s of Other a Sun-like s More Last stages can be followed on the H-R diagram: The protostar s luminosity finally decreases even as its temperature rises because it is becoming more compact.
13 Stage 6: A Newborn of s Like s of Other a Sun-like s More At stage 6, the core reaches 10 million K: nuclear fusion begins. The protostar has become a star.
14 Stage 7: A Newborn of s Like s of Other a Sun-like s More continues to contract and increase in temperature, until it is in equilibrium: the star has reached the and will remain there as long as it has H to fuse in its core.
15 Prestellar ary Tracks of s Like s of Other a Sun-like s More This H-R diagram shows the evolution of stars somewhat more and somewhat less massive than. The shape of the paths is very similar, but they wind up in different places on the.
16 of s Like s of Other a Sun-like Binary Systems: Gliese 623 If the mass of the original nebular fragment is too small, nuclear fusion will never begin. These failed stars are called brown dwarfs. Below: Hubble image of Gliese 623. This binary system may contain a brown dwarf. s More
17 of s Like s of Other Newborn Cluster: NGC 3603 Because a single interstellar cloud can produce many stars of the same age and composition, star clusters are an excellent way to study the effect of mass on stellar evolution. a Sun-like s More The cluster contains 2000 bright stars.
18 of s Like s of Other Open Cluster: Pleiades or M45 This is a young star cluster The Pleiades. The H-R diagram of its stars is on the right. This is an example of an open cluster. a Sun-like s More
19 of s Like s of Other Globular Cluster: Ω Centauri This is a globular cluster. Note the absence of massive stars, and the heavily populated Red Giant region. a Sun-like s More
20 of s Like s of Other Young s in Orion These images are believed to show a star cluster in the process of formation within the Orion nebula. a Sun-like s More Visible image dominated by emission nebula. However, IF image shows an extensive star cluster.
21 Cluster NGC 346 of s Like s of Other a Sun-like s More
22 of s Like s of Other a Sun-like s More Protostellar Collisions The presence of massive, short-lived O (T 30, 000 K) and B (T 20, 000 K) stars can profoundly affect their star cluster, as they can blow away dust and gas before it has time to collapse. This is a simulation of such a cluster.
23 Outline of s Like s of Other a Sun-like s More 1 of s Like s of Other 2 3 a Sun-like 4 5 s More 6
24 of s Like s of Other a Sun-like Equilibrium During its stay on the (steadily burning), any fluctuations in a star s condition are quickly restored Hydrostatic Equilibrium. s More
25 of s Like s of Other a Sun-like s More Equilibrium Eventually, as hydrogen in the core is consumed, the star begins to leave the. Its evolution from then on depends very much on the mass of the star: 1 Low-mass stars leave quietly. 2 High-mass stars go out with a bang!
26 Outline of s Like s of Other a Sun-like s More 1 of s Like s of Other 2 3 a Sun-like 4 5 s More 6
27 of s Like s of Other a Sun-like s More Solar Composition Change Even while it is on the, the composition of a star s core is changing. The change speeds up as the nuclear burning rate increases with time.
28 of s Like s of Other Hydrogen Shell Burning As the fuel in the core is used up, the core contracts; when it s used up, the core begins to collapse. a Sun-like s More The hydrogen begins to fuse outside the core: 1 Core has shrunk to a few tens of thousands of kilometers 2 s surface is ten times the original size
29 a Sun-like of s Like s of Other Stages of a star leaving the : a Sun-like s More
30 of s Like s of Other a Sun-like s More Stage 9: The Red-Giant Branch As the core continues to shrink, the outer layers of the star expand and cool. The star is a red giant now, extending out as far as the orbit of Mercury. Despite its slightly cooler temperature, its luminosity increases enormously due to its large size.
31 of s Like s of Other a Sun-like s More Stage 10: Helium Fusion Once the core temperature has risen to 100,000,000 K, the helium in the core starts to fuse. Helium Flash: The helium begins to fuse extremely rapidly; within hours the enormous energy output is over, and the star again reaches equilibrium.
32 of s Like s of Other Back to the Giant Branch As the helium in the core fuses to carbon, the core becomes hotter and hotter, and the helium burns faster and faster. a Sun-like s More Stage 11: The star is now similar to its condition just as it left the, except now there are two shells.
33 of s Like Stage 11: Reascending the Giant Branch s of Other a Sun-like s More The star has become a red giant for the second time: Lack of nuclear burning at the center causes the core to contract and overlying layers to expand.
34 of s Like G-type This graphic shows the entire evolution of a Sun-like star: s of Other a Sun-like s More Such stars never become hot enough for fusion past carbon to take place.
35 Outline of s Like s of Other a Sun-like s More 1 of s Like s of Other 2 3 a Sun-like 4 5 s More 6
36 of s Like s of Other There is no more outward fusion pressure being generated in the core, which continues to contract. a Sun-like s More
37 of s Like s of Other Planetary Nebulae Meanwhile, the outer layers of the star expand to form a planetary nebula: a Sun-like s More
38 of s Like s of Other a Sun-like s More The star has now two parts: 1 A small, extremely dense carbon core 2 An envelope about the size of our solar system The envelope is called a planetary nebula, even though it has nothing to do with planets early astronomers viewing the fuzzy envelope thought that it resembled a planetary system.
39 White Dwarf on H-R Diagram of s Like s of Other a Sun-like s More Stages 13 and 14: Once the nebula has gone, the remaining core is extremely dense and extremely hot, but quite small (size of Earth). It s luminous only due to its high temperature.
40 Sirius Binary System of s Like s of Other a Sun-like s More The small star Sirius B is a white-dwarf companion of the much larger and brighter Sirius A.
41 Sirius Binary System of s Like s of Other a Sun-like s More The small star Sirius B is a white-dwarf companion of the much larger and brighter Sirius A.
42 of s Like s of Other Distant White Dwarfs The Hubble Space Telescope has detected white dwarf stars (circled) in globular clusters: a Sun-like s More
43 White Dwarfs of s Like s of Other a Sun-like As the white dwarf cools, its size does not change significantly; it simply gets dimmer and dimmer, and finally ceases to glow. s More
44 of s Like s of Other a Sun-like Nova A nova is a star that flares up very suddenly and then returns slowly to its former luminosity. These novae are the result of explosions on the surface of faint white dwarf stars, caused by matter falling onto their surfaces from the atmosphere of larger binary companions. s More
45 of s Like s of Other Close Binary System A white dwarf that is part of a semidetached binary system can undergo repeated novas: a Sun-like s More
46 of s Like s of Other a Sun-like s More Nova Matter Ejection Material falls onto the white dwarf from its main-sequence companion. When enough material has accreted, fusion can reignite very suddenly, burning off the new material. Material keeps being transferred to the white dwarf, and the process repeats. Nova Persei (a) brightened by a factor of 40,000 in 1901.
47 of s Like s of Other a Sun-like s More Nova Matter Ejection Material falls onto the white dwarf from its main-sequence companion. When enough material has accreted, fusion can reignite very suddenly, burning off the new material. Material keeps being transferred to the white dwarf, and the process repeats. Nova Cygni (b) is more than 10,000 light-years away (1992).
48 Outline of s Like s of Other a Sun-like s More 1 of s Like s of Other 2 3 a Sun-like 4 5 s More 6
49 of s Like s of Other a Sun-like s More High-Mass ary Tracks This H-R diagram shows that stars more massive than follow very different paths when they leave the : M star > 2.5 M No helium flash, helium burning starts gradually M star 4 M No sharp moves on H-R diagram; it moves smoothly back and forth
50 of s Like s of Other Heavy-Element Fusion High-mass stars, like all stars, leave the when there is no more hydrogen fuel in the cores. a Sun-like s More The first few events are very similar to those in lower-mass stars: 1 First a hydrogen shell 2 Then a core burning helium to carbon, surrounded by heliumand hydrogen-burning shells.
51 of s Like s of Other a Sun-like Mass Loss from Supergiants (a) Eta Carinae is one of the most massive and most luminous stars known. An HST image shows blobs of ejected material racing away from the star at hundreds of kilometers per sec. (b) V838 Monocerotis (poorly understood red supergiant) illuminates shells of gas and dust expelled long ago. s More
52 The End of the Road of s Like s of Other a Sun-like s More
53 Outline of s Like s of Other a Sun-like s More 1 of s Like s of Other 2 3 a Sun-like 4 5 s More 6
54 of s Like s of Other a Sun-like s More A star of more than 8 solar masses can fuse elements far beyond carbon in its core, leading to a very different fate. Its path across the H-R diagram is essentially a straight line it stays at just about the same luminosity as it cools off. Eventually the star dies in a violent explosion called a supernova.
55 of s Like s of Other Light Curves A supernova is incredibly luminous, as can be seen from these curves more than a million times as bright a nova. a Sun-like s More
56 of s Like s of Other 1987A A supernova is a one-time event once it happens, there is little or nothing left of the progenitor star. a Sun-like s More
57 of s Like s of Other 1 Carbon-detonation supernova Two Types of 2 Death of a high-mass star: core collapses, then rebounds a Sun-like s More
58 of s Like s of Other a Sun-like Carbon-Detonation A white dwarf can accumulate too much mass from its binary companion. If the white dwarf s mass exceeds 1.4 solar masses, electron degeneracy can no longer keep the core from collapsing: Then carbon fusion begins throughout the star almost simultaneously, resulting in a carbon explosion. s More
59 of s Like s of Other Carbon-Detonation e leave remnants the expanding clouds of material from the explosion. a Sun-like s More The Crab nebula is a remnant from a supernova explosion that occurred in the year 1054.
60 Stellar Recycling of s Like s of Other a Sun-like s More
Lecture Outlines Chapter 20 Astronomy Today 8th Edition Chaisson/McMillan Chapter 20 Stellar Evolution Units of Chapter 20 20.1 Leaving the Main Sequence 20.2 Evolution of a Sun-Like Star 20.3 The Death
Chapter 20 Stellar Evolution Part 2. Secs. 20.4, 20.5 20.4 Evolution of Stars More Massive than the Sun It can be seen from this H-R diagram that stars more massive than the Sun follow very different paths
the nature of the universe, galaxies, and stars can be determined by observations over time by using telescopes The spectral lines of stars tell us their approximate composition Remember last year in Physics?
Guiding Questions Stellar Evolution 1. Why do astronomers think that stars evolve? 2. What kind of matter exists in the spaces between the stars? 3. What steps are involved in forming a star like the Sun?
The Formation of Stars A World of Dust The space between the stars is not completely empty, but filled with very dilute gas and dust, producing some of the most beautiful objects in the sky. We are interested
Phys 0 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 9 MULTIPLE CHOICE 1. We know that giant stars are larger in diameter than the sun because * a. they are more luminous but have about the
Star Deaths Why Do Stars Leave the Main Sequence? Running out of fuel Observing Stellar Evolution by studying Globular Cluster HR diagrams Plot stars in globular clusters in Hertzsprung-Russell diagram
FYI: The Lives of Stars E3:R6b 1. Read FYI: The Lives of Stars As you read use the spaces below to write down any information you find especially interesting. Also define the bold terms used in the text.
10/26/16 Lecture Outline 13.1 Star Birth Chapter 13: Star Stuff How do stars form? Our goals for learning: How do stars form? How massive are newborn stars? Star-Forming Clouds Stars form in dark clouds
Age of M13: 14 billion years. Mass of stars leaving the main-sequence ~0.8 solar masses Helium coreburning stars Giants Subgiants Main Sequence Here is a way to think about it. Outside of star Plenty of
STARS Instructions Students will underline the portions of the PowerPoint that are underlined. Nuclear Furnace 1. A star is like a gigantic nuclear furnace. 2. The nuclear reactions inside convert hydrogen
Life and Death of a Star Chapters 20 and 21 90 % of a stars life Most stars spend most of their lives on the main sequence. A star like the Sun, for example, after spending a few tens of millions of years
Chapter 12 Review TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 1) As a main-sequence star, the Sun's hydrogen supply should last about 10 billion years from the zero-age
Beyond Our Solar System Chapter 24 PROPERTIES OF STARS Distance Measuring a star's distance can be very difficult Stellar parallax Used for measuring distance to a star Apparent shift in a star's position
What is this? Recall what you know about the Big Bang. Most of the normal matter in the universe is made of what elements? Where do we find most of this normal matter? Interstellar medium (ISM) The universe
I. Stars have color, brightness, mass, temperature and size. II. Distances to stars are measured using stellar parallax a. The further away, the less offset b. Parallax angles are extremely small c. Measured
Properties of Stars Characteristics of Stars A constellation is an apparent group of stars originally named for mythical characters. The sky contains 88 constellations. Star Color and Temperature Color
Life and Death of a Star 2015 Name Date 1. In the main-sequence, the core is slowly shrinking because A. the mass of the star is slowly increasing B. hydrogen fusing to helium makes the core more dense
25.2 Stellar Evolution By studying stars of different ages, astronomers have been able to piece together the evolution of a star. Star Birth The birthplaces of stars are dark, cool interstellar clouds,
Stellar Evolution Review: HR Diagram Label A, B, C respectively A C B a) A: White dwarfs, B: Giants, C: Main sequence b) A: Main sequence, B: Giants, C: White dwarfs c) A: Main sequence, B: White Dwarfs,
Ay 1 Lecture 9 M7 ESO HR Diagram, Star Clusters, and Stellar Evolution 9.1 The HR Diagram Stellar Spectral Types Temperature L T Y The Hertzsprung-Russel (HR) Diagram It is a plot of stellar luminosity
Hubble Photos Credit: NASA, The Hubble Heritage Team (STScI/AURA) Heading for death. q q q q q q Leaving the main sequence End of the Sunlike star The helium core The Red-Giant Branch Helium Fusion Helium
Astro 21 first lecture The H-R H R Diagram helps us study how stars are born but also helps us study how they die. Stars spend most of their lives as main sequence stars. The core does change from hydrogen
AST 101 Introduction to Astronomy: Stars & Galaxies The H-R Diagram review So far: Stars on Main Sequence (MS) Next: - Pre MS (Star Birth) - Post MS: Giants, Super Giants, White dwarfs Star Birth We start
Prentice Hall EARTH SCIENCE Tarbuck Lutgens Chapter 25 Beyond Our Solar System 25.1 Properties of Stars Characteristics of Stars A constellation is an apparent group of stars originally named for mythical
Chapter 17 Lecture The Cosmic Perspective Seventh Edition Star Stuff Star Stuff 17.1 Lives in the Balance Our goals for learning: How does a star's mass affect nuclear fusion? How does a star's mass affect
Earth Science, 13e Tarbuck & Lutgens Beyond Our Solar System Earth Science, 13e Chapter 24 Stanley C. Hatfield Southwestern Illinois College Properties of stars Distance Distances to the stars are very
Life Cycle of a Star Video (5 min) http://www.youtube.com/watch?v=pm9cqdlqi0a The Life Cycle of Stars Solar Nebula Theory : Is the current theory of how our Solar System formed. This theory states that
High Mass Stars Dr Ken Rice High mass star formation High mass star formation is controversial! May form in the same way as low-mass stars Gravitational collapse in molecular clouds. May form via competitive
Exam # 3 Tue 12/06/2011 Astronomy 100/190Y Exploring the Universe Fall 11 Instructor: Daniela Calzetti INSTRUCTIONS: Please, use the `bubble sheet and a pencil # 2 to answer the exam questions, by marking
Protostars on the HR Diagram Once a protostar is hot enough to start, it can blow away the surrounding gas Then it is visible: crosses the on the HR diagram The more the cloud, the it will form stars Lifetimes
Star formation and Evolution 1 Star formation and Evolution Stars burn fuel to produce energy and shine so they must evolve and live through a life cycle In the Milky Way we see stars at every stage of
Guiding Questions The Birth of Stars 1 1. Why do astronomers think that stars evolve (bad use of term this is about the birth, life and death of stars and that is NOT evolution)? 2. What kind of matter
Stellar Astronomy Sample Questions for Exam 4 Chapter 15 1. Emission nebulas emit light because a) they absorb high energy radiation (mostly UV) from nearby bright hot stars and re-emit it in visible wavelengths.
Name: Period: Date: Astronomy Ch. 21 Stellar Explosions MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A surface explosion on a white dwarf, caused
Late Stages of Stellar Evolution The star enters the Asymptotic Giant Branch with an active helium shell burning and an almost dormant hydrogen shell Again the stars size and luminosity increase, leading
Chapter 12 Stellar Evolution Guidepost Stars form from the interstellar medium and reach stability fusing hydrogen in their cores. This chapter is about the long, stable middle age of stars on the main
Lecture 4 Stars The physics of stars A star begins simply as a roughly spherical ball of (mostly) hydrogen gas, responding only to gravity and it s own pressure. X-ray ultraviolet infrared radio To understand
Life of a Low-Mass Star AST 101 Introduction to Astronomy: Stars & Galaxies Planetary Nebulae White dwarfs REVIEW END STATE: PLANETARY NEBULA + WHITE DWARF WHAS IS A WHITE DWARF? Exposed core of a low-mass
Chapter 28 Stars and Their Characteristics Origin of the Universe Big Bang Theory about 10-20 bya all matter in the universe existed in a hot dense state about the size of an atom (tiny). That matter sort
The Life and Death of Stars What is a Star? A star is a sphere of plasma gas that fuses atomic nuclei in its core and so emits light The name star can also be tagged onto a body that is somewhere on the
A Star is born: The Sun SNC1D7-Space Exploring the Sun Our Sun, a star, is the most important celestial object for life on Earth. The solar nebula theory is the current theory used to explain the formation
GALAXIES AND STARS 1. Compared with our Sun, the star Betelgeuse is A smaller, hotter, and less luminous B smaller, cooler, and more luminous C larger, hotter, and less luminous D larger, cooler, and more
Goals: The Birth Of Stars How do stars form from the interstellar medium Where does star formation take place How do we induce star formation Interstellar Medium Gas and dust between stars is the interstellar
20. Stellar Death Low-mass stars undergo three red-giant stages Dredge-ups bring material to the surface Low -mass stars die gently as planetary nebulae Low -mass stars end up as white dwarfs High-mass
Stars & Galaxies Chapter 27 Modern Earth Science Chapter 27, Section 1 27.1 Characteristics of Stars Composition & Temperature Scientists use the following tools to study stars Telescope Observation Spectral
Stars & Galaxies Chapter 27 Modern Earth Science Chapter 27, Section 1 27.1 Characteristics of Stars How do astronomers determine the composition and surface temperature of a star? Composition & Temperature
Name: Block: Stellar Evolution Notes Stars mature, grow old and die. The more massive a star is, the shorter its life will be. Our Sun will live about 10 billion years. It is already 5 billion years old,
Birth & Death of Stars Objectives How are stars formed How do they die How do we measure this The Interstellar Medium (ISM) Vast clouds of gas & dust lie between stars Diffuse hydrogen clouds: dozens of
The Evolution of Binary-Star Systems If the stars in a binary-star system are relatively widely separated, their evolution proceeds much as it would have if they were not companions... If they are closer,
Astro 1050 Fri. Apr. 10, 2015 Today: Continue Ch. 13: Star Stuff Reading in Bennett: For Monday: Finish Chapter 13 Star Stuff Reminders: Ch. 12 HW now on Mastering Astronomy, due Monday. Ch. 13 will be
The Deaths of Stars 1 Guiding Questions 1. What kinds of nuclear reactions occur within a star like the Sun as it ages? 2. Where did the carbon atoms in our bodies come from? 3. What is a planetary nebula,
The Deaths of Stars 1 Guiding Questions 1. What kinds of nuclear reactions occur within a star like the Sun as it ages? 2. Where did the carbon atoms in our bodies come from? 3. What is a planetary nebula,
Stars and Galaxies 1 Characteristics of Stars 2 Star - body of gases that gives off great amounts of radiant energy as light and heat 3 Most stars look white but are actually different colors Antares -
The Evolution of Low Mass Stars Key Ideas: Low Mass = M < 4 M sun Stages of Evolution of a Low Mass star: Main Sequence star star star Asymptotic Giant Branch star Planetary Nebula phase White Dwarf star
Stellar Evolution: The Deaths of Stars Chapter Twenty-Two Guiding Questions 1. What kinds of nuclear reactions occur within a star like the Sun as it ages? 2. Where did the carbon atoms in our bodies come
The Deaths of Stars Guiding Questions 1. What kinds of nuclear reactions occur within a star like the Sun as it ages? 2. Where did the carbon atoms in our bodies come from? 3. What is a planetary nebula,
Chapter 14: The Bizarre Stellar Graveyard Assignments 2 nd Mid-term to be held Friday Nov. 3 same basic format as MT1 40 mult. choice= 80 pts. 4 short answer = 20 pts. Sample problems on web page Origin
Edwin Hubble Discovered galaxies other than the milky way. Galaxy: A collection of stars, planets, gas, and dust that are held together by gravity. Our sun and planets are in the Milky Way He noticed that
Astronomy A. Dayle Hancock firstname.lastname@example.org Small 239 Office hours: MTWR 10-11am Death of Stars Nuclear reactions in small stars How stars disperse carbon How low mass stars die The nature of white dwarfs
Lecture 11 Stellar Evolution Stars are chemical factories The Earth and all life on the Earth are made of elements forged in stars A Spiral Galaxy (Milky Way Type) 120,000 ly A few hundred billion stars
Star Stuff Star Formation Stars form in the interstellar medium Nebula in Scorpius Star Formation Stars form in the interstellar medium This contains very cold, dark clouds of dusty molecular gas Pillars
Astronomy 1504 Section 002 Astronomy 1514 Section 10 Midterm 2, Version 1 October 19, 2012 Choose the answer that best completes the question. Read each problem carefully and read through all the answers.
Chapter 12 Stellar Evolution Guidepost This chapter is the heart of any discussion of astronomy. Previous chapters showed how astronomers make observations with telescopes and how they analyze their observations
Before proceeding to Chapter 20 More on Cluster H-R diagrams: The key to the chronology of our Galaxy Below are two important HR diagrams: 1. The evolution of a number of stars all formed at the same time
11/7/11 Chapter 12: The Lives of Stars Space is Not Empty The Constellation Orion The Orion Nebula This material between the stars is called the Interstellar Medium It is very diffuse and thin. In fact
Lecture 16: The life of a low-mass star Astronomy 111 Monday October 23, 2017 Reminders Online homework #8 due Monday at 3pm Exam #2: Monday, 6 November 2017 The Main Sequence ASTR111 Lecture 16 Main sequence
HW2 Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The polarization of light passing though the dust grains shows that: 1) A) the dust grains
The Night Sky The Universe Chapter 14 Homework: All the multiple choice questions in Applying the Concepts and Group A questions in Parallel Exercises. Celestial observation dates to ancient civilizations
Chapter 12 Star Stuff How do stars form? Star-Forming Clouds Stars form in the interstellar medium This contains very cold, dark clouds of dusty molecular gas To form a star, the gas has to collapse, just
Astronomy A. Dayle Hancock email@example.com Small 239 Office hours: MTWR 10-11am Stellar Evolution Main Sequence star changes during nuclear fusion What happens when the fuel runs out Old stars and second
Stellar Evolution 17.1 Lives in the Balance Our goals for learning: How does a star's mass affect nuclear fusion? How does a star's mass affect nuclear fusion? Stellar Mass and Fusion The mass of a main-sequence
Understanding how stars evolve requires both observation and ideas from physics The Lives of Stars Because stars shine by thermonuclear reactions, they have a finite life span That is, they fuse lighter
240 points CHAPTER 29 STARS SECTION 29.1 The Sun (40 points this page) In your textbook, read about the properties of the Sun and the Sun s atmosphere. Use each of the terms below just once to complete
Late stages of stellar evolution for high-mass stars Low-mass stars lead a relatively peaceful life in their old age: although some may gently blow off their outer envelopes to form beautiful planetary
Stars and their properties: (Chapters 11 and 12) To classify stars we determine the following properties for stars: 1. Distance : Needed to determine how much energy stars produce and radiate away by using
Chapter 9 The Formation and Structure of Stars The Interstellar Medium (ISM) The space between the stars is not completely empty, but filled with very dilute gas and dust, producing some of the most beautiful
Low-mass Stellar Evolution The lives of low-mass stars And the lives of massive stars The Structure of the Sun Let s review: The Sun is held together by? The inward force is balanced by? Thinking about
1 Ch. 10: Star Formation of Planetary Systems A summary of the process by which our solar system formed, according to the nebular theory. Materials in the solar nebula. 2 3 Temperature differences in the
PHYS103 Sec 901 Hour Exam No. 3 Practice Version 1 Page: 1 PHYS103 Sec 901 Hour Exam No. 3 Practice Version 1 Page: 2 1 The HR diagram of a young, open cluster typically shows a. the entire main sequence