5) What spectral type of star that is still around formed longest ago? 5) A) F B) A C) M D) K E) O

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "5) What spectral type of star that is still around formed longest ago? 5) A) F B) A C) M D) K E) O"

Transcription

1 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 are elongated in shape. B) the dust grains are aligned by a weak interstellar magnetic field. C) the dust grains are chiefly made of iron. D) Both A and B are correct. E) All of the above are correct. 2) What makes the subject of star formation so difficult and complex? 2) A) It is so slow that no visible proof of it exists. B) Shock waves disrupt the orderly evolution of stars. C) Clouds, fragments, protostars, stars, and nebulae all interact and influence each other. D) Star formation is too expensive to study in detail. E) Stars live too long to be observed from birth to death. 3) A star (no matter what its mass) spends most of its life: 3) A) as a red giant or supergiant. B) as a protostar. C) as a main sequence star. D) as a T Tauri variable star. E) as a planetary nebula. 4) When a star's inward gravity and outward pressure are balanced, the star is said to be: 4) A) in rotational equilibrium. B) in thermal expansion. C) a stage 2 protostar. D) in gravitational collapse. E) in hydrostatic equilibrium. 5) What spectral type of star that is still around formed longest ago? 5) A) F B) A C) M D) K E) O 6) What spectral type of star that is still around formed most recently? 6) A) K B) A C) F D) M E) O 7) At which stage in a Sun-like star's life is its core the least dense? 7) A) Planetary Nebula B) Helium Fusion C) White Dwarf D) Main Sequence E) Subgiant Branch 8) Which of the following elements contained in your body is NOT formed in the cores of stars during thermonuclear fusion? A) aluminum B) carbon C) calcium D) hydrogen E) iron 8) 9) What temperature is needed to fuse helium into carbon? 9) A) 5,800 K B) one billion K

2 C) 15 million K D) 100 million K E) 100,000 K 10) The "helium flash" occurs at what stage in stellar evolution? 10) A) in the middle of the main sequence stage B) planetary nebula C) when the T Tauri bipolar jets shoot out D) horizontal branch E) red giant 11) During the hydrogen shell burning phase: 11) A) hydrogen is burning in the central core. B) helium is burning in the core. C) the core is expanding. D) the star grows more luminous. E) the star becomes less luminous. 12) A star is on the horizontal branch of the H-R diagram. Which statement is true? 12) A) It is burning both hydrogen and helium. B) The star is contracting. C) It is about to experience the helium flash. D) The star is about to return to the main sequence. E) It is burning only helium. 13) What inevitably forces a star like the Sun to evolve away from being a main sequence star? 13) A) Helium builds up in the core, while the hydrogen burning shell expands. B) The star uses up all its supply of hydrogen. C) The carbon detonation explodes it as a type I supernova. D) The core begins fusing iron. E) The core loses all its neutrinos, so all fusion ceases. 14) Just as a low-mass main sequence star runs out of fuel in its core, it actually becomes brighter. How is this possible? A) Its outer envelope is stripped away and we see the brilliant core. B) It immediately starts to fuse helium. C) It explodes. D) Helium fusion gives more energy than hydrogen fusion does, based on masses. E) The core contracts, raising the temperature and increasing the size of the region of hydrogen shell-burning. 14)

3 15) Refer to the figure above. What is the name of the path between the points labeled 8 and 9? 15) A) planetary nebula B) red giant branch C) horizontal branch D) asymptotic giant branch E) white dwarf 16) Refer to the figure above. What is the name of the path between the points labeled 10 and 11? 16) A) planetary nebula B) red giant branch C) horizontal branch D) asymptotic giant branch E) white dwarf 17) Our Sun, along with most of the stars in our neighborhood, probably formed: 17) A) at the beginning of the universe. B) hundreds of millions of years ago. C) about 10 million years ago. D) billions of years ago. E) a few million years ago. 18) What is the force that keeps a main sequence star from blowing apart? 18) A) radiation pressure B) magnetism C) gravitation D) electron degeneration pressure E) the strong force 19) Which event marks the birth of a star? 19) A) collapse of an interstellar cloud

4 B) formation of a photosphere C) instability in an interstellar cloud D) formation of the planetary nebula E) fusion of hydrogen atoms into helium atoms 20) What happens when an interstellar cloud fragment shrinks? 20) A) Temperature rises. B) Density rises. C) Pressure rises. D) It first becomes opaque. E) All of the above. 21) During a protostar's T Tauri phase, it: 21) A) begins a period of reduced activity. B) expands dramatically. C) changes its spin direction. D) lies on the main sequence. E) may develop very strong winds. 22) A newly formed protostar will radiate primarily at which wavelength? 22) A) ultraviolet B) infrared C) radio D) X-ray E) visible light 23) How long does it take for a star like our Sun to form? 23) A) 4.6 billion years B) fifty million years C) 100 thousand years D) two million years E) one billion years 24) A typical protostar may be several thousand times more luminous than the Sun. What is the source of this energy? A) the ionization of the gas as it heats up B) chemical combustion of hydrocarbons C) from the release of gravitational energy as the protostar continues to shrink D) nuclear fusion in its core E) from nearby hot stars or supernovae that have initiated the star formation process 24) 25) As a star forms, the photosphere first appears: 25) A) when contraction slows down. B) when the protostar forms. C) when nuclear fires ignite. D) when the planetary nebula is expelled. E) when the star reaches the main sequence. 26) At what stage of evolution do T Tauri stars occur? 26) A) just prior to the protostar stage B) just after the planetary nebula is expelled C) just as the collapsing cloud becomes luminous

5 D) after the star has established itself as a main sequence star E) when a protostar is on the verge of becoming a main sequence star 27) What is characteristic of a main sequence star? 27) A) The rate of nuclear energy generated in the hydrogen to helium fusing core equals the rate radiated from the surface. B) It has rapid rotation and a strong stellar wind. C) It has a mass less than the Sun's. D) Nuclear fusion in the core varies due to the amount of gravitational contraction that occurs and which heavy elements are produced. E) All of the above are correct. 28) On an H-R diagram, a protostar would be: 28) A) above and near the upper left of the main sequence. B) below and near the right side of the main sequence. C) above and to the right of the main sequence. D) below and to the left of the main sequence. E) on the main sequence at the extreme lower right. 29) Interstellar gas is composed of: 29) A) 90% hydrogen, 9% helium by weight. B) some hydrogen, but mainly carbon dioxide. C) 10% hydrogen, 90% helium by numbers of atoms. D) ammonia, methane, and water vapor. E) only hydrogen. 30) What effect do even thin clouds of dust have on light passing through them? 30) A) It dims and reddens the light of all more distant stars. B) Its motion causes the light of stars beyond to twinkle. C) The light that passes through them is blue shifted due to the cloud's approach. D) Even a little can completely block all light, such as the Horsehead Nebula. E) Its motion causes all light to be redshifted as it passes through these clouds. 31) The of light passing through thin dust clouds lets us map the Galaxy's magnetic field. 31) A) polarization B) absorption C) ionization D) granulation E) diffraction 32) Which of the following describes the shape of dust particles, based on polarization of light? 32) A) diamonds B) cubes C) rodlike D) spheres E) disks 33) Some regions along the plane of the Milky Way appear dark because: 33) A) stars in that region are hidden by interstellar gas. B) many black holes absorb all light from those directions. C) there are no stars in these areas. D) many brown dwarfs in those areas absorb light which they turn into heat. E) stars in that region are hidden by dark dust particles. 34) Due to absorption of shorter wavelengths by interstellar dust clouds, distant stars appear: 34) A) brighter.

6 B) redder. C) larger. D) bluer. E) to have a higher radial velocity. 35) Which statement is true about the interstellar medium? 35) A) Gas contains a lot of carbon atoms. B) Dust is spread uniformly through the galaxy. C) Gas obscures the light from distant stars. D) We know more about the gas than the dust. E) Dust blocks the longest electromagnetic wavelengths. 36) The spectra of interstellar gas clouds show that they have the same basic composition as: 36) A) Earth's atmosphere. B) interstellar dust. C) stars. D) the Martian polar caps. E) asteroids. 37) The density of interstellar dust is very low, yet it still blocks starlight because: 37) A) the dust particles are about the same size as the light waves they absorb. B) it is so cold it absorbs higher energy photons. C) there is 100 times more opaque gas than dust present in the ISM. D) ice particles reflect all light back toward their stars, not toward us. E) the dust particles are irregular in shape. 38) The overall dimming of starlight by interstellar matter is called: 38) A) absorption. B) scattering. C) extinction. D) emission. E) reddening. 39) In the Milky Way galaxy, gas and dust are found: 39) A) in emission nebulae. B) in neutral hydrogen clouds. C) in dark nebulae. D) in molecular clouds. E) everywhere. 40) Which is the least dense? 40) A) interstellar gas B) the atmosphere of the Sun C) the atmosphere of Earth D) the atmosphere of Jupiter E) interstellar dust

7 1) D 2) E 3) C 4) E 5) C 6) E 7) D 8) D 9) D 10) E 11) D 12) A 13) A 14) E 15) B 16) D 17) D 18) C 19) E 20) E 21) E 22) B 23) B 24) C 25) B 26) E 27) A 28) C 29) A 30) A 31) A 32) C 33) E 34) B 35) D 36) C 37) A 38) C 39) E 40) E

Physics Homework Set 2 Sp 2015

Physics Homework Set 2 Sp 2015 1) A large gas cloud in the interstellar medium that contains several type O and B stars would appear to us as 1) A) a reflection nebula. B) a dark patch against a bright background. C) a dark nebula.

More information

Chapter 11 Review. 1) Light from distant stars that must pass through dust arrives bluer than when it left its star. 1)

Chapter 11 Review. 1) Light from distant stars that must pass through dust arrives bluer than when it left its star. 1) Chapter 11 Review TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 1) Light from distant stars that must pass through dust arrives bluer than when it left its star. 1)

More information

Astronomy Ch. 20 Stellar Evolution. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Astronomy Ch. 20 Stellar Evolution. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Name: Period: Date: Astronomy Ch. 20 Stellar Evolution MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A star (no matter what its mass) spends

More information

Astronomy Ch. 20 Stellar Evolution. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Astronomy Ch. 20 Stellar Evolution. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Name: Period: Date: Astronomy Ch. 20 Stellar Evolution MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A star (no matter what its mass) spends

More information

Guiding Questions. Stellar Evolution. Stars Evolve. Interstellar Medium and Nebulae

Guiding Questions. Stellar Evolution. Stars Evolve. Interstellar Medium and Nebulae 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?

More information

AST 101 INTRODUCTION TO ASTRONOMY SPRING MIDTERM EXAM 2 TEST VERSION 1 ANSWERS

AST 101 INTRODUCTION TO ASTRONOMY SPRING MIDTERM EXAM 2 TEST VERSION 1 ANSWERS AST 101 INTRODUCTION TO ASTRONOMY SPRING 2008 - MIDTERM EXAM 2 TEST VERSION 1 ANSWERS Multiple Choice. In the blanks provided before each question write the letter for the phrase that best answers the

More information

The Birth Of Stars. How do stars form from the interstellar medium Where does star formation take place How do we induce star formation

The Birth Of Stars. How do stars form from the interstellar medium Where does star formation take place How do we induce star formation 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

More information

Chapter 12 Review. 2) About 90% of the star's total life is spent on the main sequence. 2)

Chapter 12 Review. 2) About 90% of the star's total life is spent on the main sequence. 2) 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

More information

Stellar Astronomy Sample Questions for Exam 4

Stellar Astronomy Sample Questions for Exam 4 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.

More information

Recall what you know about the Big Bang.

Recall what you know about the Big Bang. 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

More information

Chapter 9. The Formation and Structure of Stars

Chapter 9. The Formation and Structure of Stars 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

More information

The Ecology of Stars

The Ecology of Stars The Ecology of Stars We have been considering stars as individuals; what they are doing and what will happen to them Now we want to look at their surroundings And their births 1 Interstellar Matter Space

More information

Beyond the Solar System 2006 Oct 17 Page 1 of 5

Beyond the Solar System 2006 Oct 17 Page 1 of 5 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

More information

Astronomy 1504 Section 002 Astronomy 1514 Section 10 Midterm 2, Version 1 October 19, 2012

Astronomy 1504 Section 002 Astronomy 1514 Section 10 Midterm 2, Version 1 October 19, 2012 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.

More information

Atoms and Star Formation

Atoms and Star Formation Atoms and Star Formation What are the characteristics of an atom? Atoms have a nucleus of protons and neutrons about which electrons orbit. neutrons protons electrons 0 charge +1 charge 1 charge 1.67 x

More information

Chapter 11 The Formation of Stars

Chapter 11 The Formation of Stars Chapter 11 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.

More information

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.

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. 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

More information

18. Stellar Birth. Initiation of Star Formation. The Orion Nebula: A Close-Up View. Interstellar Gas & Dust in Our Galaxy

18. Stellar Birth. Initiation of Star Formation. The Orion Nebula: A Close-Up View. Interstellar Gas & Dust in Our Galaxy 18. Stellar Birth Star observations & theories aid understanding Interstellar gas & dust in our galaxy Protostars form in cold, dark nebulae Protostars evolve into main-sequence stars Protostars both gain

More information

Guiding Questions. The Birth of Stars

Guiding Questions. The Birth of Stars 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

More information

Clicker Question: Clicker Question: What is the expected lifetime for a G2 star (one just like our Sun)?

Clicker Question: Clicker Question: What is the expected lifetime for a G2 star (one just like our Sun)? How Long do Stars Live (as Main Sequence Stars)? A star on Main Sequence has fusion of H to He in its core. How fast depends on mass of H available and rate of fusion. Mass of H in core depends on mass

More information

AST Section 2: Test 2

AST Section 2: Test 2 AST1002 - Section 2: Test 2 Date: 11/05/2009 Name: Equations: E = m c 2 Question 1: The Sun is a stable star because 1. gravity balances forces from pressure. (!) Miniquiz 7, Q3 2. the rate of fusion equals

More information

Why Do Stars Leave the Main Sequence? Running out of fuel

Why Do Stars Leave the Main Sequence? Running out of fuel 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

More information

25.2 Stellar Evolution. By studying stars of different ages, astronomers have been able to piece together the evolution of a star.

25.2 Stellar Evolution. By studying stars of different ages, astronomers have been able to piece together the evolution of a star. 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,

More information

Stellar Evolution: Outline

Stellar Evolution: Outline Stellar Evolution: Outline Interstellar Medium (dust) Hydrogen and Helium Small amounts of Carbon Dioxide (makes it easier to detect) Massive amounts of material between 100,000 and 10,000,000 solar masses

More information

PHYS103 Sec 901 Hour Exam No. 3 Page: 1

PHYS103 Sec 901 Hour Exam No. 3 Page: 1 PHYS103 Sec 901 Hour Exam No. 3 Page: 1 PHYS103 Sec 901 Hour Exam No. 3 Page: 2 1 The star alpha-centauri C has moved across the sky by 3853 seconds of arc during the last thousand years - slightly more

More information

PHYS103 Sec 901 Hour Exam No. 3 Page: 1

PHYS103 Sec 901 Hour Exam No. 3 Page: 1 PHYS103 Sec 901 Hour Exam No. 3 Page: 1 PHYS103 Sec 901 Hour Exam No. 3 Page: 2 1 A steady X-ray signal with sudden bursts lasting a few seconds each is probably caused by a. a supermassive star. b. a

More information

Chapter 33 The History of a Star. Introduction. Radio telescopes allow us to look into the center of the galaxy. The milky way

Chapter 33 The History of a Star. Introduction. Radio telescopes allow us to look into the center of the galaxy. The milky way Chapter 33 The History of a Star Introduction Did you read chapter 33 before coming to class? A. Yes B. No You can see about 10,000 stars with the naked eye. The milky way Radio telescopes allow us to

More information

Phys 100 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 9

Phys 100 Astronomy (Dr. Ilias Fernini) Review Questions for Chapter 9 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

More information

Protostars evolve into main-sequence stars

Protostars evolve into main-sequence stars 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

More information

Stellar evolution Part I of III Star formation

Stellar evolution Part I of III Star formation Stellar evolution Part I of III Star formation 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

More information

Number of Stars: 100 billion (10 11 ) Mass : 5 x Solar masses. Size of Disk: 100,000 Light Years (30 kpc)

Number of Stars: 100 billion (10 11 ) Mass : 5 x Solar masses. Size of Disk: 100,000 Light Years (30 kpc) THE MILKY WAY GALAXY Type: Spiral galaxy composed of a highly flattened disk and a central elliptical bulge. The disk is about 100,000 light years (30kpc) in diameter. The term spiral arises from the external

More information

Energy. mosquito lands on your arm = 1 erg. Firecracker = 5 x 10 9 ergs. 1 stick of dynamite = 2 x ergs. 1 ton of TNT = 4 x ergs

Energy. mosquito lands on your arm = 1 erg. Firecracker = 5 x 10 9 ergs. 1 stick of dynamite = 2 x ergs. 1 ton of TNT = 4 x ergs Energy mosquito lands on your arm = 1 erg Firecracker = 5 x 10 9 ergs 1 stick of dynamite = 2 x 10 13 ergs 1 ton of TNT = 4 x 10 16 ergs 1 atomic bomb = 1 x 10 21 ergs Magnitude 8 earthquake = 1 x 10 26

More information

ASTRONOMY 1 EXAM 3 a Name

ASTRONOMY 1 EXAM 3 a Name ASTRONOMY 1 EXAM 3 a Name Identify Terms - Matching (20 @ 1 point each = 20 pts.) Multiple Choice (25 @ 2 points each = 50 pts.) Essays (choose 3 of 4 @ 10 points each = 30 pt 1.Luminosity D 8.White dwarf

More information

Explain how the sun converts matter into energy in its core. Describe the three layers of the sun s atmosphere.

Explain how the sun converts matter into energy in its core. Describe the three layers of the sun s atmosphere. Chapter 29 and 30 Explain how the sun converts matter into energy in its core. Describe the three layers of the sun s atmosphere. Explain how sunspots are related to powerful magnetic fields on the sun.

More information

Remember from Stefan-Boltzmann that 4 2 4

Remember from Stefan-Boltzmann that 4 2 4 Lecture 17 Review Most stars lie on the Main sequence of an H&R diagram including the Sun, Sirius, Procyon, Spica, and Proxima Centauri. This figure is a plot of logl versus logt. The main sequence is

More information

AST 101 Introduction to Astronomy: Stars & Galaxies

AST 101 Introduction to Astronomy: Stars & Galaxies 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

More information

Chapter 16 Lecture. The Cosmic Perspective Seventh Edition. Star Birth Pearson Education, Inc.

Chapter 16 Lecture. The Cosmic Perspective Seventh Edition. Star Birth Pearson Education, Inc. Chapter 16 Lecture The Cosmic Perspective Seventh Edition Star Birth 2014 Pearson Education, Inc. Star Birth The dust and gas between the star in our galaxy is referred to as the Interstellar medium (ISM).

More information

Lifespan on the main sequence. Lecture 9: Post-main sequence evolution of stars. Evolution on the main sequence. Evolution after the main sequence

Lifespan on the main sequence. Lecture 9: Post-main sequence evolution of stars. Evolution on the main sequence. Evolution after the main sequence Lecture 9: Post-main sequence evolution of stars Lifetime on the main sequence Shell burning and the red giant phase Helium burning - the horizontal branch and the asymptotic giant branch The death of

More information

Chapter 11 The Formation and Structure of Stars

Chapter 11 The Formation and Structure of Stars Chapter 11 The Formation and Structure of Stars Guidepost The last chapter introduced you to the gas and dust between the stars that are raw material for new stars. Here you will begin putting together

More information

Stellar Birth. Stellar Formation. A. Interstellar Clouds. 1b. What is the stuff. Astrophysics: Stellar Evolution. A. Interstellar Clouds (Nebulae)

Stellar Birth. Stellar Formation. A. Interstellar Clouds. 1b. What is the stuff. Astrophysics: Stellar Evolution. A. Interstellar Clouds (Nebulae) Astrophysics: Stellar Evolution 1 Stellar Birth Stellar Formation A. Interstellar Clouds (Nebulae) B. Protostellar Clouds 2 C. Protostars Dr. Bill Pezzaglia Updated: 10/02/2006 A. Interstellar Clouds 1.

More information

Comparing a Supergiant to the Sun

Comparing a Supergiant to the Sun The Lifetime of Stars Once a star has reached the main sequence stage of it life, it derives its energy from the fusion of hydrogen to helium Stars remain on the main sequence for a long time and most

More information

Astronomy 104: Second Exam

Astronomy 104: Second Exam Astronomy 104: Second Exam Stephen Lepp October 29, 2014 Each question is worth 2 points. Write your name on this exam and on the scantron. Short Answer A The Sun is powered by converting hydrogen to what?

More information

The Formation of Stars

The Formation of Stars 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

More information

10/26/ Star Birth. Chapter 13: Star Stuff. How do stars form? Star-Forming Clouds. Mass of a Star-Forming Cloud. Gravity Versus Pressure

10/26/ Star Birth. Chapter 13: Star Stuff. How do stars form? Star-Forming Clouds. Mass of a Star-Forming Cloud. Gravity Versus Pressure 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

More information

The Life Cycles of Stars. Modified from Information provided by: Dr. Jim Lochner, NASA/GSFC

The Life Cycles of Stars. Modified from Information provided by: Dr. Jim Lochner, NASA/GSFC The Life Cycles of Stars Modified from Information provided by: Dr. Jim Lochner, NASA/GSFC Twinkle, Twinkle, Little Star... What do you see? How I Wonder What You Are... Stars have: Different Colors -

More information

Stars and their properties: (Chapters 11 and 12)

Stars and their properties: (Chapters 11 and 12) 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

More information

Ch. 29 The Stars Stellar Evolution

Ch. 29 The Stars Stellar Evolution Ch. 29 The Stars 29.3 Stellar Evolution Basic Structure of Stars Mass effects The more massive a star is, the greater the gravity pressing inward, and the hotter and more dense the star must be inside

More information

Chapter 10 The Interstellar Medium

Chapter 10 The Interstellar Medium Chapter 10 The Interstellar Medium Guidepost You have begun your study of the sun and other stars, but now it is time to study the thin gas and dust that drifts through space between the stars. This chapter

More information

Guiding Questions. The Deaths of Stars. Pathways of Stellar Evolution GOOD TO KNOW. Low-mass stars go through two distinct red-giant stages

Guiding Questions. The Deaths of Stars. Pathways of Stellar Evolution GOOD TO KNOW. Low-mass stars go through two distinct red-giant stages 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,

More information

The Deaths of Stars 1

The Deaths of Stars 1 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,

More information

Stars & Galaxies. Chapter 27, Section 1. Composition & Temperature. Chapter 27 Modern Earth Science Characteristics of Stars

Stars & Galaxies. Chapter 27, Section 1. Composition & Temperature. Chapter 27 Modern Earth Science Characteristics of Stars 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

More information

Stars & Galaxies. Chapter 27 Modern Earth Science

Stars & Galaxies. Chapter 27 Modern Earth Science 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

More information

Chapter 14. Stellar Evolution I. The exact sequence of evolutionary stages also depends on the mass of a star.

Chapter 14. Stellar Evolution I. The exact sequence of evolutionary stages also depends on the mass of a star. Chapter 14 Stellar Evolution I I. Introduction Stars evolve in the sense that they pass through different stages of a stellar life cycle that is measured in billions of years. The longer the amount of

More information

Stellar Evolution: The Deaths of Stars. Guiding Questions. Pathways of Stellar Evolution. Chapter Twenty-Two

Stellar Evolution: The Deaths of Stars. Guiding Questions. Pathways of Stellar Evolution. Chapter Twenty-Two 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

More information

The Stars. Chapter 14

The Stars. Chapter 14 The Stars Chapter 14 Great Idea: The Sun and other stars use nuclear fusion reactions to convert mass into energy. Eventually, when a star s nuclear fuel is depleted, the star must burn out. Chapter Outline

More information

Guiding Questions. The Deaths of Stars. Pathways of Stellar Evolution GOOD TO KNOW. Low-mass stars go through two distinct red-giant stages

Guiding Questions. The Deaths of Stars. Pathways of Stellar Evolution GOOD TO KNOW. Low-mass stars go through two distinct red-giant stages 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,

More information

Life and Death of a Star 2015

Life and Death of a Star 2015 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

More information

PHYS 1401: Descriptive Astronomy Notes: Chapter 12

PHYS 1401: Descriptive Astronomy Notes: Chapter 12 CHAPTER 12: STELLAR EVOLUTION 12.1: LEAVING THE MAIN SEQUENCE Stars and the Scientific Method You cannot observe a single star from birth to death You can observe a lot of stars in a very short period

More information

Review: HR Diagram. Label A, B, C respectively

Review: HR Diagram. Label A, B, C respectively 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,

More information

Life and Death of a Star. Chapters 20 and 21

Life and Death of a Star. Chapters 20 and 21 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

More information

AST1002 Spring 2018 Final Exam Review Questions

AST1002 Spring 2018 Final Exam Review Questions AST1002 Spring 2018 Final Exam Review Questions Douglas H. Laurence Department of Physical Sciences, Broward College, Davie, FL 33314 Abstract This is a set of review questions for the upcoming midterm

More information

Chapter 12: The Lives of Stars. How do we know it s there? Three Kinds of Nebulae 11/7/11. 1) Emission Nebulae 2) Reflection Nebulae 3) Dark Nebulae

Chapter 12: The Lives of Stars. How do we know it s there? Three Kinds of Nebulae 11/7/11. 1) Emission Nebulae 2) Reflection Nebulae 3) Dark Nebulae 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

More information

LIFE CYCLE OF A STAR

LIFE CYCLE OF A STAR LIFE CYCLE OF A STAR First stage = Protostar PROTOSTAR Cloud of gas and dust many light-years across Gravity tries to pull the materials together Eventually, at the center of the ball of dust and gas,

More information

Astronomy Ch. 21 Stellar Explosions. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Astronomy Ch. 21 Stellar Explosions. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 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

More information

ASTR Midterm 1 Phil Armitage, Bruce Ferguson

ASTR Midterm 1 Phil Armitage, Bruce Ferguson ASTR 1120-001 Midterm 1 Phil Armitage, Bruce Ferguson FIRST MID-TERM EXAM FEBRUARY 16 th 2006: Closed books and notes, 1 hour. Please PRINT your name and student ID on the places provided on the scan sheet.

More information

Astronomy. Stellar Evolution

Astronomy. Stellar Evolution Astronomy A. Dayle Hancock adhancock@wm.edu 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

More information

The Electromagnetic Spectrum

The Electromagnetic Spectrum The Electromagnetic Spectrum Three Kinds of Spectra Sun: The Nearest Star Radius 696,000 km 109 Re Mass 2 x 10^30 kg 300,000 Me Density 1400 kg/m^3 Luminosity 3.8x10^26 Watts (board calc.) Comp. 70% H,

More information

The Universe. is space and everything in it.

The Universe. is space and everything in it. The Universe is space and everything in it. Galaxies A galaxy is a supercluster of stars, gas, and dust that are held together by gravity. There are three main types of galaxies: Irregular Elliptical Spiral

More information

The Life and Death of Stars

The Life and Death of Stars 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

More information

Stellar Evolution. Stars are chemical factories The Earth and all life on the Earth are made of elements forged in stars

Stellar Evolution. Stars are chemical factories The Earth and all life on the Earth are made of elements forged in stars 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

More information

What is a star? A body of gases that gives off tremendous amounts of energy in the form of light & heat. What star is closest to the earth?

What is a star? A body of gases that gives off tremendous amounts of energy in the form of light & heat. What star is closest to the earth? Stars What is a star? A body of gases that gives off tremendous amounts of energy in the form of light & heat. What star is closest to the earth? Answer: The SUN It s about 150,000,000 km from earth =

More information

The Night Sky. The Universe. The Celestial Sphere. Stars. Chapter 14

The Night Sky. The Universe. The Celestial Sphere. Stars. Chapter 14 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

More information

Exam #2 Review Sheet. Part #1 Clicker Questions

Exam #2 Review Sheet. Part #1 Clicker Questions Exam #2 Review Sheet Part #1 Clicker Questions 1) The energy of a photon emitted by thermonuclear processes in the core of the Sun takes thousands or even millions of years to emerge from the surface because

More information

Chapter 17: Stellar Evolution

Chapter 17: Stellar Evolution Astr 2310 Thurs. Mar. 30, 2017 Today s Topics Chapter 17: Stellar Evolution Birth of Stars and Pre Main Sequence Evolution Evolution on and off the Main Sequence Solar Mass Stars Massive Stars Low Mass

More information

Stars and Galaxies 1

Stars and Galaxies 1 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 -

More information

Birth & Death of Stars

Birth & Death of Stars 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

More information

Life Cycle of a Star Worksheet

Life Cycle of a Star Worksheet Life Cycle of a Star Worksheet A STAR IS BORN STAGES COMMON TO ALL STARS All stars start as a nebula. A nebula is a large cloud of gas and dust. Gravity can pull some of the gas and dust in a nebula together.

More information

Exam # 3 Tue 12/06/2011 Astronomy 100/190Y Exploring the Universe Fall 11 Instructor: Daniela Calzetti

Exam # 3 Tue 12/06/2011 Astronomy 100/190Y Exploring the Universe Fall 11 Instructor: Daniela Calzetti 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

More information

the nature of the universe, galaxies, and stars can be determined by observations over time by using telescopes

the nature of the universe, galaxies, and stars can be determined by observations over time by using telescopes 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?

More information

Chapters 12 and 13 Review: The Life Cycle and Death of Stars. How are stars born, and how do they die? 4/1/2009 Habbal Astro Lecture 27 1

Chapters 12 and 13 Review: The Life Cycle and Death of Stars. How are stars born, and how do they die? 4/1/2009 Habbal Astro Lecture 27 1 Chapters 12 and 13 Review: The Life Cycle and Death of Stars How are stars born, and how do they die? 4/1/2009 Habbal Astro 110-01 Lecture 27 1 Stars are born in molecular clouds Clouds are very cold:

More information

Topics for Today s Class

Topics for Today s Class Foundations of Astronomy 13e Seeds Chapter 11 Formation of Stars and Structure of Stars Topics for Today s Class 1. Making Stars from the Interstellar Medium 2. Evidence of Star Formation: The Orion Nebula

More information

Physics Homework Set I Su2015

Physics Homework Set I Su2015 1) The particles which enter into chemical reactions are the atom's: 1) _ A) protons. B) positrons. C) mesons. D) electrons. E) neutrons. 2) Which of the following type of electromagnetic radiation has

More information

Midterm Results. The Milky Way in the Infrared. The Milk Way from Above (artist conception) 3/2/10

Midterm Results. The Milky Way in the Infrared. The Milk Way from Above (artist conception) 3/2/10 Lecture 13 : The Interstellar Medium and Cosmic Recycling Midterm Results A2020 Prof. Tom Megeath The Milky Way in the Infrared View from the Earth: Edge On Infrared light penetrates the clouds and shows

More information

ASTR-1020: Astronomy II Course Lecture Notes Section VI

ASTR-1020: Astronomy II Course Lecture Notes Section VI ASTR-1020: Astronomy II Course Lecture Notes Section VI Dr. Donald G. Luttermoser East Tennessee State University Edition 4.0 Abstract These class notes are designed for use of the instructor and students

More information

Earth Science, 13e Tarbuck & Lutgens

Earth Science, 13e Tarbuck & Lutgens 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

More information

8/30/2010. Classifying Stars. Classifying Stars. Classifying Stars

8/30/2010. Classifying Stars. Classifying Stars. Classifying Stars Classifying Stars In the early 1900s, Ejnar Hertzsprung and Henry Russell made some important observations. They noticed that, in general, stars with higher temperatures also have brighter absolute magnitudes.

More information

HR Diagram, Star Clusters, and Stellar Evolution

HR Diagram, Star Clusters, and Stellar Evolution 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

More information

Properties of Stars. Characteristics of Stars

Properties of Stars. Characteristics of Stars 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

More information

AST 101 Introduction to Astronomy: Stars & Galaxies

AST 101 Introduction to Astronomy: Stars & Galaxies The H-R Diagram review So far: AST 101 Introduction to Astronomy: Stars & Galaxies - Stars on Main Sequence (MS) - Pre MS (Star Birth) Next: - Post MS: Giants, Super Giants, White dwarfs Evolution of Low

More information

NSCI 314 LIFE IN THE COSMOS

NSCI 314 LIFE IN THE COSMOS NSCI 314 LIFE IN THE COSMOS 2 BASIC ASTRONOMY, AND STARS AND THEIR EVOLUTION Dr. Karen Kolehmainen Department of Physics CSUSB COURSE WEBPAGE: http://physics.csusb.edu/~karen MOTIONS IN THE SOLAR SYSTEM

More information

10/29/2009. The Lives And Deaths of Stars. My Office Hours: Tuesday 3:30 PM - 4:30 PM 206 Keen Building. Stellar Evolution

10/29/2009. The Lives And Deaths of Stars. My Office Hours: Tuesday 3:30 PM - 4:30 PM 206 Keen Building. Stellar Evolution 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 Test 2: 11/05/2009 of s Like s of Other a Sun-like s More

More information

Review Questions for the new topics that will be on the Final Exam

Review Questions for the new topics that will be on the Final Exam Review Questions for the new topics that will be on the Final Exam Be sure to review the lecture-tutorials and the material we covered on the first three exams. How does speed differ from velocity? Give

More information

Stellar Evolution Notes

Stellar Evolution Notes 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,

More information

Life Cycle of a Star - Activities

Life Cycle of a Star - Activities Name: Class Period: Life Cycle of a Star - Activities A STAR IS BORN STAGES COMMON TO ALL STARS All stars start as a nebula. A nebula is a large cloud of gas and dust. Gravity can pull some of the gas

More information

Birth and Death of Stars. Birth of Stars. Gas and Dust Clouds. Astronomy 110 Class 11

Birth and Death of Stars. Birth of Stars. Gas and Dust Clouds. Astronomy 110 Class 11 Birth and Death of Stars Astronomy 110 Class 11 Birth of Stars Start in cloud of gas and dust Contraction and Fragmentation Gravitational collapse and heating Protostar and disk Main Sequence Star Gas

More information

Chapter 19: The Evolution of Stars

Chapter 19: The Evolution of Stars Chapter 19: The Evolution of Stars Why do stars evolve? (change from one state to another) Energy Generation fusion requires fuel, fuel is depleted [fig 19.2] at higher temperatures, other nuclear process

More information

Ch. 16 & 17: Stellar Evolution and Death

Ch. 16 & 17: Stellar Evolution and Death Ch. 16 & 17: Stellar Evolution and Death Stars have lives: born, evolve, die Mass determines stellar evolution: Really Low Mass (0.08 to 0.4 M sun ) Low Mass: (0.4 to 4 M sun ) Long lives High Mass (4

More information

The Interstellar Medium. Papillon Nebula. Neutral Hydrogen Clouds. Interstellar Gas. The remaining 1% exists as interstellar grains or

The Interstellar Medium. Papillon Nebula. Neutral Hydrogen Clouds. Interstellar Gas. The remaining 1% exists as interstellar grains or The Interstellar Medium About 99% of the material between the stars is in the form of a gas The remaining 1% exists as interstellar grains or interstellar dust If all the interstellar gas were spread evenly,

More information