Chapter 21 Astronomy Today 7th Edition Chaisson/McMillan

Size: px
Start display at page:

Download "Chapter 21 Astronomy Today 7th Edition Chaisson/McMillan"

Transcription

1 Lecture Outlines Chapter 21 Astronomy Today 7th Edition Chaisson/McMillan

2 Chapter 21 Stellar Explosions

3 Units of Chapter Life after Death for White Dwarfs 21.2 The End of a High-Mass Star 21.3 Supernovae Supernova 1987A 21.4 The Formation of the Elements 21.5 The Cycle of Stellar Evolution

4 21.1 Life after Death for White Dwarfs A nova is a star that flares up very suddenly and then returns slowly to its former luminosity:

5 21.1 Life after Death for White Dwarfs A white dwarf that is part of a semidetached binary system can undergo repeated novas.

6 21.1 Life after Death for White Dwarfs 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, as illustrated here:

7 21.1 Life after Death for White Dwarfs This series of images shows ejected material expanding away from a star after a nova explosion:

8 21.2 The End of a High-Mass Star A high-mass star can continue to fuse elements in its core right up to iron (after which the fusion reaction is energetically unfavored). As heavier elements are fused, the reactions go faster and the stage is over more quickly. A 20-solar-mass star will burn carbon for about 10,000 years, but its iron core lasts less than a day.

9 21.2 The End of a High-Mass Star This graph shows the relative stability of nuclei. On the left, nuclei gain energy through fusion; on the right they gain it through fission: Iron is the crossing point; when the core has fused to iron, no more fusion can take place

10 21.2 The End of a High-Mass Star The inward pressure is enormous, due to the high mass of the star. There is nothing stopping the star from collapsing further; it does so very rapidly, in a giant implosion. As it continues to become more and more dense, the protons and electrons react with one another to become neutrons: p + e n + neutrino

11 21.2 The End of a High-Mass Star The neutrinos escape; the neutrons are compressed together until the whole star has the density of an atomic nucleus, about 1015 kg/m3. The collapse is still going on; it compresses the neutrons further until they recoil in an enormous explosion as a supernova.

12 21.3 Supernovae A supernova is incredibly luminous as can be seen from these curves and more than a million times as bright as a nova:

13 21.3 Supernovae A supernova is a one-time event once it happens, there is little or nothing left of the progenitor star. There are two different types of supernovae, both equally common: Type I, which is a carbon-detonation supernova, and Type II, which is the death of a high-mass star just described

14 21.3 Supernovae Carbon-detonation supernova: white dwarf that has accumulated too much mass from binary companion If the white dwarf s mass exceeds 1.4 solar masses, electron degeneracy can no longer keep the core from collapsing. Carbon fusion begins throughout the star almost simultaneously, resulting in a carbon explosion.

15 21.3 Supernovae This graphic illustrates the two different types of supernovae:

16 21.3 Supernovae Supernovae leave remnants the expanding clouds of material from the explosion. The Crab nebula is a remnant from a supernova explosion that occurred in the year 1054.

17 21.3 Supernovae The velocities of the material in the Crab nebula can be extrapolated back, using Doppler shifts, to the original explosion.

18 21.3 Supernovae This is the Vela supernova remnant: Extrapolation shows it exploded about 9000 BCE

19 Discovery 21-1: Supernova 1987A Supernovae are rare; there has not been one in our galaxy for about 400 years. A supernova, called SN1987A, did occur in the Large Magellanic Cloud, a neighboring galaxy, in Its light curve is somewhat atypical:

20 Discovery 21-1: Supernova 1987A A cloud of glowing gas is now visible around SN1987A, and a small central object is becoming discernible:

21 21.4 The Formation of the Elements There are 81 stable and 10 radioactive elements that exist on our planet. Where did they come from? This graph shows the relative abundances of different elements in the universe:

22 21.4 The Formation of the Elements Some of these elements are formed during normal stellar fusion. Here, three helium nuclei fuse to form carbon:

23 21.4 The Formation of the Elements Carbon can then fuse, either with itself or with alpha particles, to form more nuclei:

24 21.4 The Formation of the Elements The elements that can be formed through successive alphaparticle fusion are more abundant than those created by other fusion reactions:

25 21.4 The Formation of the Elements The last nucleus in the alpha-particle chain is nickel-56, which is unstable and quickly decays to cobalt-56 and then to iron56. Iron-56 is the most stable nucleus, so it neither fuses nor decays. However, within the cores of the most massive stars, neutron capture can create heavier elements, all the way up to bismuth-209. The heaviest elements are made during the first few seconds of a supernova explosion.

26 21.4 The Formation of the Elements This theory of formation of new elements in supernova explosions produces a light curve that agrees quite well with observed curves:

27 21.5 The Cycle of Stellar Evolution Star formation is cyclical: Stars form, evolve, and die. In dying, they send heavy elements into the interstellar medium. These elements then become parts of new stars. And so it goes.

28 Summary of Chapter 21 A nova is a star that suddenly brightens and gradually fades; it is a white dwarf whose larger partner continually transfers material to it. Stars greater than eight solar masses can have fusion in their cores going all the way up to iron, which is stable against further fusion. The star continues to collapse after the iron core is found, implodes, and then explodes as a supernova.

29 Summary of Chapter 21 (cont.) Two types of supernovae: Type I, a carbon-detonation supernova Type II, a core-collapse supernova All elements heavier than helium are formed in stars: Elements up to bismuth-209 are formed in stellar cores during fusion Heavier elements are created during supernova explosions

30 Process of Science/ Concept Checks Chapter 21 Astronomy Today 7th Edition Chaisson/McMillan

31

32 No, because it is of low mass and not a member of a binary-star system.

33

34 Because iron cannot fuse to produce energy. As a result, no further nuclear reactions are possible, and the core s equilibrium cannot be restored.

35

36 Because the two types of supernova differ in their spectra and their light curves, making it impossible to explain them in terms of a single phenomenon.

37

38 Because they are readily formed by helium capture, a process common in evolved stars. Other elements (with masses not multiples of four) had to form via less common reactions involving proton and neutron capture.

39

40 Because it is responsible for creating and dispersing all the heavy elements out of which we are made. In addition, it may also have played an important role in triggering the collapse of the interstellar cloud from which our solar system formed.

41 Lecture Outlines Chapter 22 Astronomy Today 7th Edition Chaisson/McMillan

42 Chapter 22 Neutron Stars and Black Holes

43 Units of Chapter Neutron Stars 22.2 Pulsars 22.3 Neutron-Star Binaries 22.4 Gamma-Ray Bursts 22.5 Black Holes 22.6 Einstein s Theories of Relativity Special Relativity

44 Units of Chapter 22 (cont.) 22.7 Space Travel Near Black Holes 22.8 Observational Evidence for Black Holes Tests of General Relativity Gravity Waves: A New Window on the Universe

45 22.1 Neutron Stars After a Type I supernova, little or nothing remains of the original star. After a Type II supernova, part of the core may survive. It is very dense as dense as an atomic nucleus and is called a neutron star.

46 22.1 Neutron Stars Neutron stars, although they have 1 3 solar masses, are so dense that they are very small. This image shows a 1-solar-mass neutron star, about 10 km in diameter, compared to Manhattan:

47 22.1 Neutron Stars Other important properties of neutron stars (beyond mass and size): Rotation as the parent star collapses, the neutron core spins very rapidly, conserving angular momentum. Typical periods are fractions of a second. Magnetic field again as a result of the collapse, the neutron star s magnetic field becomes enormously strong.

48 22.2 Pulsars The first pulsar was discovered in It emitted extraordinarily regular pulses; nothing like it had ever been seen before. After some initial confusion, it was realized that this was a neutron star, spinning very rapidly.

49 22.2 Pulsars But why would a neutron star flash on and off? This figure illustrates the lighthouse effect responsible: Strong jets of matter are emitted at the magnetic poles. If the rotation axis is not the same as the magnetic axis, the two beams will sweep out circular paths. If the Earth lies in one of those paths, we will see the star pulse.

50 22.2 Pulsars Pulsars radiate their energy away quite rapidly; the radiation weakens and stops in a few tens of millions of years, making the neutron star virtually undetectable. Pulsars also will not be visible on Earth if their jets are not pointing our way.

51 22.2 Pulsars There is a pulsar at the center of the Crab Nebula; the images show it in the off and on states. The disk and jets are also visible:

52 22.2 Pulsars The Crab pulsar also pulses in the gamma-ray spectrum:

53 22.3 Neutron-Star Binaries Bursts of X-rays have been observed near the center of our galaxy. A typical one appears below, as imaged in the X-ray spectrum:

54 22.3 Neutron-Star Binaries These X-ray bursts are thought to originate on neutron stars that have binary partners. The process is similar to a nova, but much more energy is emitted due to the extremely strong gravitational field of the neutron star.

55 22.3 Neutron-Star Binaries Most pulsars have periods between 0.03 and 0.3 seconds, but a new class of pulsar was discovered in the early 1980s: the millisecond pulsar.

56 22.3 Neutron-Star Binaries Millisecond pulsars are thought to be spun-up by matter falling in from a companion. This globular cluster has been found to have 108 separate X-ray sources, about half of which are thought to be millisecond pulsars:

57 22.3 Neutron-Star Binaries In 1992, a pulsar was discovered whose period had unexpected, but very regular, variations. These variations were thought to be consistent with a planet, which must have been picked up by the neutron star, not the progenitor star:

58 22.4 Gamma-Ray Bursts Gamma-ray bursts also occur, and were first spotted by satellites looking for violations of nuclear test-ban treaties. This map of where the bursts have been observed shows no clumping of bursts anywhere, particularly not within the Milky Way. Therefore, the bursts must originate from outside our Galaxy.

59 22.4 Gamma-Ray Bursts These are some sample luminosity curves for gamma-ray bursts:

60 22.4 Gamma-Ray Bursts Distance measurements of some gamma bursts show them to be very far away 2 billion parsecs for the first one measured. Occasionally the spectrum of a burst can be measured, allowing distance determination:

61 22.4 Gamma-Ray Bursts Two models merging neutron stars or a hypernova have been proposed as the source of gamma-ray bursts:

62 22.5 Black Holes The mass of a neutron star cannot exceed about 3 solar masses. If a core remnant is more massive than that, nothing will stop its collapse, and it will become smaller and smaller and denser and denser. Eventually, the gravitational force is so intense that even light cannot escape. The remnant has become a black hole.

63 22.5 Black Holes The radius at which the escape speed from the black hole equals the speed of light is called the Schwarzschild radius. The Earth s Schwarzschild radius is about a centimeter; the Sun s is about 3 km. Once the black hole has collapsed, the Schwarzschild radius takes on another meaning it is the event horizon. Nothing within the event horizon can escape the black hole.

64 22.6 Einstein s Theories of Relativity Special relativity: 1. The speed of light is the maximum possible speed, and it is always measured to have the same value by all observers:

65 22.6 Einstein s Theories of Relativity Special relativity (cont.): 2. There is no absolute frame of reference, and no absolute state of rest. 3. Space and time are not independent but are unified as spacetime.

66 22.6 Einstein s Theories of Relativity General relativity: It is impossible to tell from within a closed system whether one is in a gravitational field or accelerating.

67 22.6 Einstein s Theories of Relativity Matter tends to warp spacetime, and in doing so redefines straight lines (the path a light beam would take): A black hole occurs when the indentation caused by the mass of the hole becomes infinitely deep.

68 More Precisely 22-1: Special Relativity In the late 19th century, Michelson and Morley did an experiment to measure the variation in the speed of light with respect to the direction of the Earth s motion around the Sun. They found no variation light always traveled at the same speed. This later became the foundation of special relativity. Taking the speed of light to be constant leads to some counterintuitive effects length contraction, time dilation, the relativity of simultaneity, and the mass equivalent of energy.

69 22.7 Space Travel Near Black Holes The gravitational effects of a black hole are unnoticeable outside of a few Schwarzschild radii black holes do not suck in material any more than an extended mass would.

70 22.7 Space Travel Near Black Holes Matter encountering a black hole will experience enormous tidal forces that will both heat it enough to radiate, and tear it apart:

71 22.7 Space Travel Near Black Holes A probe nearing the event horizon of a black hole will be seen by observers as experiencing a dramatic redshift as it gets closer, so that time appears to be going more and more slowly as it approaches the event horizon. This is called a gravitational redshift it is not due to motion, but to the large gravitational fields present. The probe, however, does not experience any such shifts; time would appear normal to anyone inside.

72 22.7 Space Travel Near Black Holes (cont.) Similarly, a photon escaping from the vicinity of a black hole will use up a lot of energy doing so; it cannot slow down, but its wavelength gets longer and longer

73 22.7 Space Travel Near Black Holes What s inside a black hole? No one knows, of course; present theory predicts that the mass collapses until its radius is zero and its density is infinite, but it is unlikely that this actually happens. Until we learn more about what happens in such extreme conditions, the interiors of black holes will remain a mystery.

74 22.8 Observational Evidence for Black Holes Black holes cannot be observed directly, as their gravitational fields will cause light to bend around them.

75 22.8 Observational Evidence for Black Holes This bright star has an unseen companion that is a strong X-ray emitter called Cygnus X-1, which is thought to be a black hole:

76 22.8 Observational Evidence for Black Holes The existence of black-hole binary partners for ordinary stars can be inferred by the effect the holes have on the star s orbit, or by radiation from infalling matter.

77 22.8 Observational Evidence for Black Holes Cygnus X-1 is a very strong black-hole candidate: Its visible partner is about 25 solar masses. The system s total mass is about 35 solar masses, so the X-ray source must be about 10 solar masses. Hot gas appears to be flowing from the visible star to an unseen companion. Short time-scale variations indicate that the source must be very small.

78 22.8 Observational Evidence for Black Holes There are several other blackhole candidates as well, with characteristics similar to those of Cygnus X-1. The centers of many galaxies contain supermassive black holes about 1 million solar masses.

79 22.8 Observational Evidence for Black Holes Recently, evidence for intermediate-mass black holes has been found; these are about 100 to 1000 solar masses. Their origin is not well understood.

80 More Precisely 22-1: Tests of General Relativity Deflection of starlight by the sun s gravity was measured during the solar eclipse of 1919; the results agreed with the predictions of general relativity.

81 More Precisely 22-1: Tests of General Relativity Another prediction the orbit of Mercury should precess due to general relativistic effects near the Sun; again, the measurement agreed with the prediction.

82 Discovery 22-1: Gravity Waves: A New Window on the Universe General relativity predicts that orbiting objects should lose energy by emitting gravitational radiation. The amount of energy is tiny, and these waves have not yet been observed directly. However, a neutron-star binary system has been observed (two neutron stars); the orbits of the stars are slowing at just the rate predicted if gravity waves are carrying off the lost energy.

83 Discovery 22-1: Gravity Waves: A New Window on the Universe This figure shows LIGO, the Laser Interferometric Gravitywave Observatory, designed to detect gravitational waves. It has been operating since 2003, but no waves have been detected yet.

84 Summary of Chapter 22 Supernova may leave behind a neutron star. Neutron stars are very dense, spin rapidly, and have intense magnetic fields. Neutron stars may appear as pulsars due to the lighthouse effect. A neutron star in a close binary may become an X-ray burster or a millisecond pulsar. Gamma-ray bursts are probably due to two neutron stars colliding or hypernova.

85 Summary of Chapter 22 (cont.) If core remnant is more than about 3 solar masses, it collapses into black hole. We need general relativity to describe black holes; it describes gravity as the warping of spacetime. Anything entering within the event horizon of a black hole cannot escape. The distance from the event horizon to the singularity is called the Schwarzschild radius.

86 Summary of Chapter 22 (cont.) A distant observer would see an object entering black hole subject to extreme gravitational redshift and time dilation. Material approaching a black hole will emit strong Xrays. A few such X-ray sources have been found and are black-hole candidates.

87 Process of Science/ Concept Checks Chapter 22 Astronomy Today 7th Edition Chaisson/McMillan

88

89 No only Type II supernovae. According to theory, the rebounding central core of the original star in a Type II supernova becomes a neutron star.

90

91 Because (1) not all supernovae form neutron stars, (2) the pulses are beamed, so not all pulsing neutron stars are visible from Earth, and (3) pulsars spin down and become too faint to observe after a few tens of millions of years.

92

93 Some X-ray sources are binaries containing accreting neutron stars, which may be in the process of being spun up to form millisecond pulsars.

94

95 They are energetic bursts of gamma rays, roughly isotropically distributed on the sky, occurring about once per day. They pose a challenge because they are very distant, and hence extremely luminous, but their energy originates in a region less than a few hundred kilometers across. There also appear to be two distinct types, with different energy generation mechanisms.

96

97 Newton s theory describes gravity as a force produced by a massive object that influences all other massive objects. Einstein s relativity describes gravity as a curvature of space-time produced by a massive object; that curvature then determines the trajectories of all particles matter or radiation in the universe.

98

99 Because the object would appear to take infinitely long to reach the event horizon, and its light would be infinitely redshifted by the time it got there.

100

101 By observing their gravitational effects on other objects, and from the X rays emitted as matter plunges toward the event horizon.

Lecture Outlines. Chapter 22. Astronomy Today 8th Edition Chaisson/McMillan Pearson Education, Inc.

Lecture Outlines. Chapter 22. Astronomy Today 8th Edition Chaisson/McMillan Pearson Education, Inc. Lecture Outlines Chapter 22 Astronomy Today 8th Edition Chaisson/McMillan Chapter 22 Neutron Stars and Black Holes Units of Chapter 22 22.1 Neutron Stars 22.2 Pulsars 22.3 Neutron-Star Binaries 22.4 Gamma-Ray

More information

Chapter 13 2/19/2014. Lecture Outline Neutron Stars. Neutron Stars and Black Holes Neutron Stars. Units of Chapter

Chapter 13 2/19/2014. Lecture Outline Neutron Stars. Neutron Stars and Black Holes Neutron Stars. Units of Chapter 13.1 Neutron Stars Lecture Outline Chapter 13 Neutron Stars and After a Type I supernova, little or nothing remains of the original star. After a Type II supernova, part of the core may survive. It is

More information

Chapter 21 Stellar Explosions

Chapter 21 Stellar Explosions Chapter 21 Stellar Explosions Units of Chapter 21 21.1 XXLife after Death for White Dwarfs (not on exam) 21.2 The End of a High-Mass Star 21.3 Supernovae Supernova 1987A The Crab Nebula in Motion 21.4

More information

The Evolution of Binary-Star Systems

The Evolution of Binary-Star Systems 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,

More information

Chapter 18 The Bizarre Stellar Graveyard

Chapter 18 The Bizarre Stellar Graveyard Chapter 18 The Bizarre Stellar Graveyard 18.1 White Dwarfs Our goals for learning What is a white dwarf? What can happen to a white dwarf in a close binary system? What is a white dwarf? White Dwarfs White

More information

Chapter 14: The Bizarre Stellar Graveyard

Chapter 14: The Bizarre Stellar Graveyard Lecture Outline Chapter 14: The Bizarre Stellar Graveyard 14.1 White Dwarfs Our goals for learning: What is a white dwarf? What can happen to a white dwarf in a close binary system? What is a white dwarf?

More information

Physics HW Set 3 Spring 2015

Physics HW Set 3 Spring 2015 1) If the Sun were replaced by a one solar mass black hole 1) A) life here would be unchanged. B) we would still orbit it in a period of one year. C) all terrestrial planets would fall in immediately.

More information

Chapter 18 The Bizarre Stellar Graveyard. White Dwarfs. What is a white dwarf? Size of a White Dwarf White Dwarfs

Chapter 18 The Bizarre Stellar Graveyard. White Dwarfs. What is a white dwarf? Size of a White Dwarf White Dwarfs Chapter 18 The Bizarre Stellar Graveyard 18.1 White Dwarfs Our goals for learning What is a white dwarf? What can happen to a white dwarf in a close binary system? What is a white dwarf? White Dwarfs White

More information

11/1/17. Important Stuff (Section 001: 9:45 am) Important Stuff (Section 002, 1:00 pm) 14.1 White Dwarfs. Chapter 14: The Bizarre Stellar Graveyard

11/1/17. Important Stuff (Section 001: 9:45 am) Important Stuff (Section 002, 1:00 pm) 14.1 White Dwarfs. Chapter 14: The Bizarre Stellar Graveyard 11/1/17 Important Stuff (Section 001: 9:45 am) The Second Midterm is Thursday, November 9 The Second Midterm will be given in a different room: Willey 175 Bring 2 pencils and a photo-id. In accordance

More information

11/1/16. Important Stuff (Section 001: 9:45 am) Important Stuff (Section 002, 1:00 pm) 14.1 White Dwarfs. Chapter 14: The Bizarre Stellar Graveyard

11/1/16. Important Stuff (Section 001: 9:45 am) Important Stuff (Section 002, 1:00 pm) 14.1 White Dwarfs. Chapter 14: The Bizarre Stellar Graveyard Important Stuff (Section 001: 9:45 am) The Second Midterm is Thursday, November 10 The Second Midterm will be given in a different room: Willey 175 Bring 2 pencils and a photo-id. In accordance with the

More information

Chapter 18 Lecture. The Cosmic Perspective Seventh Edition. The Bizarre Stellar Graveyard Pearson Education, Inc.

Chapter 18 Lecture. The Cosmic Perspective Seventh Edition. The Bizarre Stellar Graveyard Pearson Education, Inc. Chapter 18 Lecture The Cosmic Perspective Seventh Edition The Bizarre Stellar Graveyard The Bizarre Stellar Graveyard 18.1 White Dwarfs Our goals for learning: What is a white dwarf? What can happen to

More information

Supernovae, Neutron Stars, Pulsars, and Black Holes

Supernovae, Neutron Stars, Pulsars, and Black Holes Supernovae, Neutron Stars, Pulsars, and Black Holes Massive stars and Type II supernovae Massive stars (greater than 8 solar masses) can create core temperatures high enough to burn carbon and heavier

More information

NEUTRON STARS, GAMMA RAY BURSTS, and BLACK HOLES (chap. 22 in textbook)

NEUTRON STARS, GAMMA RAY BURSTS, and BLACK HOLES (chap. 22 in textbook) NEUTRON STARS, GAMMA RAY BURSTS, and BLACK HOLES (chap. 22 in textbook) Neutron Stars For carbon detonation SN probably no remnant For core-collapse SN remnant is a neutron-degenerate core neutron star

More information

White dwarfs are the remaining cores of dead stars. Electron degeneracy pressure supports them against the crush of gravity. The White Dwarf Limit

White dwarfs are the remaining cores of dead stars. Electron degeneracy pressure supports them against the crush of gravity. The White Dwarf Limit The Bizarre Stellar Graveyard Chapter 18 Lecture The Cosmic Perspective 18.1 White Dwarfs Our goals for learning: What is a white dwarf? What can happen to a white dwarf in a close binary system? Seventh

More information

Astronomy Ch. 22 Neutron Stars and Black Holes. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

Astronomy Ch. 22 Neutron Stars and Black Holes. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Name: Period: Date: Astronomy Ch. 22 Neutron Stars and Black Holes MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) In a neutron star, the core

More information

Chapter 13 Notes The Deaths of Stars Astronomy Name: Date:

Chapter 13 Notes The Deaths of Stars Astronomy Name: Date: Chapter 13 Notes The Deaths of Stars Astronomy Name: Date: I. The End of a Star s Life When all the fuel in a star is used up, will win over pressure and the star will die nuclear fuel; gravity High-mass

More information

Neutron Stars, Black Holes, Pulsars and More

Neutron Stars, Black Holes, Pulsars and More Neutron Stars, Black Holes, Pulsars and More October 30, 2002 1) Star Clusters 2) Type II Supernova 3) Neutron Stars 4) Black Holes 5) More Gravity Announcements Extra Credit there is an extra credit assignment

More information

Protostars on the HR Diagram. Lifetimes of Stars. Lifetimes of Stars: Example. Pressure-Temperature Thermostat. Hydrostatic Equilibrium

Protostars on the HR Diagram. Lifetimes of Stars. Lifetimes of Stars: Example. Pressure-Temperature Thermostat. Hydrostatic Equilibrium 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

More information

Special Relativity. Principles of Special Relativity: 1. The laws of physics are the same for all inertial observers.

Special Relativity. Principles of Special Relativity: 1. The laws of physics are the same for all inertial observers. Black Holes Special Relativity Principles of Special Relativity: 1. The laws of physics are the same for all inertial observers. 2. The speed of light is the same for all inertial observers regardless

More information

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. HW3 Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A surface explosion on a white dwarf, caused by falling matter from the atmosphere of

More information

Life and Evolution of a Massive Star. M ~ 25 M Sun

Life and Evolution of a Massive Star. M ~ 25 M Sun Life and Evolution of a Massive Star M ~ 25 M Sun Birth in a Giant Molecular Cloud Main Sequence Post-Main Sequence Death The Main Sequence Stars burn H in their cores via the CNO cycle About 90% of a

More information

The Bizarre Stellar Graveyard

The Bizarre Stellar Graveyard The Bizarre Stellar Graveyard 18.1 White Dwarfs Our goals for learning: What is a white dwarf? What can happen to a white dwarf in a close binary system? What is a white dwarf? White Dwarfs White dwarfs

More information

Chapter 14. Outline. Neutron Stars and Black Holes. Note that the following lectures include. animations and PowerPoint effects such as

Chapter 14. Outline. Neutron Stars and Black Holes. Note that the following lectures include. animations and PowerPoint effects such as Note that the following lectures include animations and PowerPoint effects such as fly ins and transitions that require you to be in PowerPoint's Slide Show mode (presentation mode). Chapter 14 Neutron

More information

First: Some Physics. Tides on the Earth. Lecture 11: Stellar Remnants: White Dwarfs, Neutron Stars, and Black Holes A2020 Prof. Tom Megeath. 1.

First: Some Physics. Tides on the Earth. Lecture 11: Stellar Remnants: White Dwarfs, Neutron Stars, and Black Holes A2020 Prof. Tom Megeath. 1. Lecture 11: Stellar Remnants: White Dwarfs, Neutron Stars, and Black Holes A2020 Prof. Tom Megeath First: Some Physics 1. Tides 2. Degeneracy Pressure Concept 1: How does gravity cause tides? R F tides

More information

Chapter 14: The Bizarre Stellar Graveyard. Copyright 2010 Pearson Education, Inc.

Chapter 14: The Bizarre Stellar Graveyard. Copyright 2010 Pearson Education, Inc. 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

More information

Stars with Mⵙ go through two Red Giant Stages

Stars with Mⵙ go through two Red Giant Stages Astronomy A. Dayle Hancock adhancock@wm.edu 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

More information

Neutron Stars. Properties of Neutron Stars. Formation of Neutron Stars. Chapter 14. Neutron Stars and Black Holes. Topics for Today s Class

Neutron Stars. Properties of Neutron Stars. Formation of Neutron Stars. Chapter 14. Neutron Stars and Black Holes. Topics for Today s Class Foundations of Astronomy 13e Seeds Phys1403 Introductory Astronomy Instructor: Dr. Goderya Chapter 14 Neutron Stars and Black Holes Cengage Learning 2016 Topics for Today s Class Neutron Stars What is

More information

The Stellar Graveyard Neutron Stars & White Dwarfs

The Stellar Graveyard Neutron Stars & White Dwarfs The Stellar Graveyard Neutron Stars & White Dwarfs White Dwarfs White dwarfs are the remaining cores of low-mass (M < 8M sun ) stars Electron degeneracy pressure supports them against gravity Density ~

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

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

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

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

A100 Exploring the Universe: Stellar Remnants. Martin D. Weinberg UMass Astronomy

A100 Exploring the Universe: Stellar Remnants. Martin D. Weinberg UMass Astronomy A100 Exploring the Universe: Stellar Remnants Martin D. Weinberg UMass Astronomy astron100-mdw@courses.umass.edu October 28, 2014 Read: S3, Chap 18 10/28/14 slide 1 Exam #2: November 04 One week from today!

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

Chapter 18 Reading Quiz Clickers. The Cosmic Perspective Seventh Edition. The Bizarre Stellar Graveyard Pearson Education, Inc.

Chapter 18 Reading Quiz Clickers. The Cosmic Perspective Seventh Edition. The Bizarre Stellar Graveyard Pearson Education, Inc. Reading Quiz Clickers The Cosmic Perspective Seventh Edition The Bizarre Stellar Graveyard 18.1 White Dwarfs What is a white dwarf? What can happen to a white dwarf in a close binary system? What supports

More information

Dead & Variable Stars

Dead & Variable Stars Dead & Variable Stars Supernovae Death of massive Stars As the core collapses, it overshoots and bounces A shock wave travels through the star and blows off the outer layers, including the heavy elements

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

Pulsars - a new tool for astronomy and physics

Pulsars - a new tool for astronomy and physics 1 Reading: Chapter 24, Sect. 24.5-24.6; Chap. 20, Chap. 25, Sec. 25.1 Exam 2: Thursday, March 22; essay question given on Tuesday, March 20 Last time:death of massive stars - supernovae & neutron stars

More information

Lecture Outlines. Chapter 20. Astronomy Today 8th Edition Chaisson/McMillan Pearson Education, Inc.

Lecture Outlines. Chapter 20. Astronomy Today 8th Edition Chaisson/McMillan Pearson Education, Inc. 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

More information

The Death of Stars. Today s Lecture: Post main-sequence (Chapter 13, pages ) How stars explode: supernovae! White dwarfs Neutron stars

The Death of Stars. Today s Lecture: Post main-sequence (Chapter 13, pages ) How stars explode: supernovae! White dwarfs Neutron stars The Death of Stars Today s Lecture: Post main-sequence (Chapter 13, pages 296-323) How stars explode: supernovae! White dwarfs Neutron stars White dwarfs Roughly the size of the Earth with the mass of

More information

ASTR Midterm 2 Phil Armitage, Bruce Ferguson

ASTR Midterm 2 Phil Armitage, Bruce Ferguson ASTR 1120-001 Midterm 2 Phil Armitage, Bruce Ferguson SECOND MID-TERM EXAM MARCH 21 st 2006: Closed books and notes, 1 hour. Please PRINT your name and student ID on the places provided on the scan sheet.

More information

21. Neutron Stars. The Crab Pulsar: On & Off. Intensity Variations of a Pulsar

21. Neutron Stars. The Crab Pulsar: On & Off. Intensity Variations of a Pulsar 21. Neutron Stars Neutron stars were proposed in the 1930 s Pulsars were discovered in the 1960 s Pulsars are rapidly rotating neutron stars Pulsars slow down as they age Neutron stars are superfluid &

More information

Stellar Evolution - Chapter 12 and 13. The Lives and Deaths of Stars White dwarfs, neutron stars and black holes

Stellar Evolution - Chapter 12 and 13. The Lives and Deaths of Stars White dwarfs, neutron stars and black holes Stellar Evolution - Chapter 12 and 13 The Lives and Deaths of Stars White dwarfs, neutron stars and black holes During the early stages of a star formation the objects are called a protostars. The internal

More information

Stellar Explosions (ch. 21)

Stellar Explosions (ch. 21) Stellar Explosions (ch. 21) First, a review of low-mass stellar evolution by means of an illustration I showed in class. You should be able to talk your way through this diagram and it should take at least

More information

Notes for Wednesday, July 16; Sample questions start on page 2 7/16/2008

Notes for Wednesday, July 16; Sample questions start on page 2 7/16/2008 Notes for Wednesday, July 16; Sample questions start on page 2 7/16/2008 Wed, July 16 MW galaxy, then review. Start with ECP3Ch14 2 through 8 Then Ch23 # 8 & Ch 19 # 27 & 28 Allowed Harlow Shapely to locate

More information

Astronomy 110: SURVEY OF ASTRONOMY. 11. Dead Stars. 1. White Dwarfs and Supernovae. 2. Neutron Stars & Black Holes

Astronomy 110: SURVEY OF ASTRONOMY. 11. Dead Stars. 1. White Dwarfs and Supernovae. 2. Neutron Stars & Black Holes Astronomy 110: SURVEY OF ASTRONOMY 11. Dead Stars 1. White Dwarfs and Supernovae 2. Neutron Stars & Black Holes Low-mass stars fight gravity to a standstill by becoming white dwarfs degenerate spheres

More information

Gravity simplest. fusion

Gravity simplest. fusion Gravity simplest fusion The life of a star has a complex relationship with gravity: 1. Gravity is what brings the original dust together to make a star 2. Gravity wants to crush the star Gravity pulls

More information

Brock University. Test 1, February, 2017 Number of pages: 9 Course: ASTR 1P02 Number of Students: 480 Date of Examination: February 6, 2017

Brock University. Test 1, February, 2017 Number of pages: 9 Course: ASTR 1P02 Number of Students: 480 Date of Examination: February 6, 2017 Brock University Test 1, February, 2017 Number of pages: 9 Course: ASTR 1P02 Number of Students: 480 Date of Examination: February 6, 2017 Number of hours: 50 min Time of Examination: 18:00 18:50 Instructor:

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

Planetary Nebulae evolve to White Dwarf Stars

Planetary Nebulae evolve to White Dwarf Stars Planetary Nebulae evolve to White Dwarf Stars Planetary Nebulae When Red Giant exhausts its He fuel the C core contracts Low & medium-mass stars don t have enough gravitational energy to heat to core 6

More information

Neutron Stars. But what happens to the super-dense core? It faces two possible fates:

Neutron Stars. But what happens to the super-dense core? It faces two possible fates: Neutron Stars When a massive star runs out of fuel, its core collapses from the size of the Earth to a compact ball of neutrons just ten miles or so across. Material just outside the core falls onto this

More information

Black Holes. Over the top? Black Holes. Gravity s Final Victory. Einstein s Gravity. Near Black holes escape speed is greater than the speed of light

Black Holes. Over the top? Black Holes. Gravity s Final Victory. Einstein s Gravity. Near Black holes escape speed is greater than the speed of light Black Holes Over the top? What if the remnant core is very massive? M core > 2-3 M sun (original star had M > 18 M sun ) Neutron degeneracy pressure fails. Nothing can stop gravitational collapse. Collapses

More information

Brock University. Test 1, January, 2015 Number of pages: 9 Course: ASTR 1P02 Number of Students: 500 Date of Examination: January 29, 2015

Brock University. Test 1, January, 2015 Number of pages: 9 Course: ASTR 1P02 Number of Students: 500 Date of Examination: January 29, 2015 Brock University Test 1, January, 2015 Number of pages: 9 Course: ASTR 1P02 Number of Students: 500 Date of Examination: January 29, 2015 Number of hours: 50 min Time of Examination: 18:00 15:50 Instructor:

More information

Neutron Stars. Chapter 14: Neutron Stars and Black Holes. Neutron Stars. What s holding it up? The Lighthouse Model of Pulsars

Neutron Stars. Chapter 14: Neutron Stars and Black Holes. Neutron Stars. What s holding it up? The Lighthouse Model of Pulsars Neutron Stars Form from a 8-20 M Sun star Chapter 14: Neutron Stars and Black Holes Leftover 1.4-3 M Sun core after supernova Neutron Stars consist entirely of neutrons (no protons) Neutron Star (tennis

More information

Astronomy 104: Stellar Astronomy

Astronomy 104: Stellar Astronomy Astronomy 104: Stellar Astronomy Lecture 19: Stellar Remnants (Hanging Out with the Degenerates) Spring Semester 2013 Dr. Matt Craig 1 1 Things To Do Today and Next Time Chapter 12.2 (Neutron Stars) Chapter

More information

ASTR-101 4/4/2018 Stellar Evolution: Part II Lecture 19

ASTR-101 4/4/2018 Stellar Evolution: Part II Lecture 19 ASTR-101 4/4/2018 Stellar Evolution: Part II Lecture 19 WHEN S THE NEXT TEST?!?!?!? If anyone is following the syllabus, you know that it says there is a test today. The test will be on April 11 th (a

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

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

Lecture 18 : Black holes. Astronomy 111

Lecture 18 : Black holes. Astronomy 111 Lecture 18 : Black holes Astronomy 111 Gravity's final victory A star more massive than about 18 M sun would leave behind a post-supernova core this is larger than 2-3 M sun :Neutron degeneracy pressure

More information

Astronomy Stars, Galaxies and Cosmology Exam 3. Please PRINT full name

Astronomy Stars, Galaxies and Cosmology Exam 3. Please PRINT full name Astronomy 132 - Stars, Galaxies and Cosmology Exam 3 Please PRINT full name Also, please sign the honor code: I have neither given nor have I received help on this exam The following exam is intended to

More information

2) On a Hertzsprung-Russell diagram, where would you find red giant stars? A) upper right B) lower right C) upper left D) lower left

2) On a Hertzsprung-Russell diagram, where would you find red giant stars? A) upper right B) lower right C) upper left D) lower left Multiple choice test questions 2, Winter Semester 2015. Based on parts covered after mid term. Essentially on Ch. 12-2.3,13.1-3,14,16.1-2,17,18.1-2,4,19.5. You may use a calculator and the useful formulae

More information

A100 Exploring the Universe: Stellar Remnants. Martin D. Weinberg UMass Astronomy

A100 Exploring the Universe: Stellar Remnants. Martin D. Weinberg UMass Astronomy A100 Exploring the Universe: Stellar Remnants Martin D. Weinberg UMass Astronomy astron100-mdw@courses.umass.edu March 24, 2015 Read: S3, Chap 18 03/24/15 slide 1 Exam #2: March 31 One week from today!

More information

Astronomy Notes Chapter 13.notebook. April 11, 2014

Astronomy Notes Chapter 13.notebook. April 11, 2014 All stars begin life in a similar way the only difference is in the rate at which they move through the various stages (depends on the star's mass). A star's fate also depends on its mass: 1) Low Mass

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

Assignment 9. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.

Assignment 9. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. Assignment 9 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. The astrophysicist who first calculated the highest mass that a dying star can

More information

measured to be 10,000K, its small mass and faint luminosity did not make sense in the context of the mass-luminosity relation for stars.

measured to be 10,000K, its small mass and faint luminosity did not make sense in the context of the mass-luminosity relation for stars. 8.4 White Dwarfs As an asymptotic giant branch star becomes larger and more luminous, the rate at which is loses mass also increases. For stars less than 8 solar masses, a strong stellar wind develops

More information

Evolution of High Mass stars

Evolution of High Mass stars Evolution of High Mass stars Neutron Stars A supernova explosion of a M > 8 M Sun star blows away its outer layers. The central core will collapse into a compact object of ~ a few M Sun. Pressure becomes

More information

This class: Life cycle of high mass stars Supernovae Neutron stars, pulsars, pulsar wind nebulae, magnetars Quark-nova stars Gamma-ray bursts (GRBs)

This class: Life cycle of high mass stars Supernovae Neutron stars, pulsars, pulsar wind nebulae, magnetars Quark-nova stars Gamma-ray bursts (GRBs) This class: Life cycle of high mass stars Supernovae Neutron stars, pulsars, pulsar wind nebulae, magnetars Quark-nova stars Gamma-ray bursts (GRBs)!1 Cas$A$ All$Image$&$video$credits:$Chandra$X7ray$ Observatory$

More information

BANG! Structure of a White Dwarf NO energy production gravity = degenerate gas pressure as it cools, becomes Black Dwarf. Lives of High Mass Stars

BANG! Structure of a White Dwarf NO energy production gravity = degenerate gas pressure as it cools, becomes Black Dwarf. Lives of High Mass Stars Structure of a White Dwarf NO energy production gravity = degenerate gas pressure as it cools, becomes Black Dwarf Mass Limit for White Dwarfs S. Chandrasekhar (1983 Nobel Prize) -calculated max. mass

More information

Accretion Disks. Review: Stellar Remnats. Lecture 12: Black Holes & the Milky Way A2020 Prof. Tom Megeath 2/25/10. Review: Creating Stellar Remnants

Accretion Disks. Review: Stellar Remnats. Lecture 12: Black Holes & the Milky Way A2020 Prof. Tom Megeath 2/25/10. Review: Creating Stellar Remnants Lecture 12: Black Holes & the Milky Way A2020 Prof. Tom Megeath Review: Creating Stellar Remnants Binaries may be destroyed in white dwarf supernova Binaries be converted into black holes Review: Stellar

More information

Astro 1050 Fri. Apr. 10, 2015

Astro 1050 Fri. Apr. 10, 2015 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

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

Chapter 13: The Stellar Graveyard

Chapter 13: The Stellar Graveyard Chapter 13: The Stellar Graveyard Habbal Astro110 http://chandra.harvard.edu/photo/2001/1227/index.html Chapter 13 Lecture 26 1 Low mass star High mass (>8 M sun ) star Ends as a white dwarf. Ends in a

More information

Neutron Stars. Neutron Stars and Black Holes. The Crab Pulsar. Discovery of Pulsars. The Crab Pulsar. Light curves of the Crab Pulsar.

Neutron Stars. Neutron Stars and Black Holes. The Crab Pulsar. Discovery of Pulsars. The Crab Pulsar. Light curves of the Crab Pulsar. Chapter 11: Neutron Stars and Black Holes A supernova explosion of an M > 8 M sun star blows away its outer layers. Neutron Stars The central core will collapse into a compact object of ~ a few M sun.

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

Astronomy. Chapter 15 Stellar Remnants: White Dwarfs, Neutron Stars, and Black Holes

Astronomy. Chapter 15 Stellar Remnants: White Dwarfs, Neutron Stars, and Black Holes Astronomy Chapter 15 Stellar Remnants: White Dwarfs, Neutron Stars, and Black Holes are hot, compact stars whose mass is comparable to the Sun's and size to the Earth's. A. White dwarfs B. Neutron stars

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

High Mass Stars and then Stellar Graveyard 7/16/09. Astronomy 101

High Mass Stars and then Stellar Graveyard 7/16/09. Astronomy 101 High Mass Stars and then Stellar Graveyard 7/16/09 Astronomy 101 Astronomy Picture of the Day Astronomy 101 Something Cool Betelgeuse Astronomy 101 Outline for Today Astronomy Picture of the Day Something

More information

Astronomy 114. Lecture 22: Neutron Stars. Martin D. Weinberg. UMass/Astronomy Department

Astronomy 114. Lecture 22: Neutron Stars. Martin D. Weinberg. UMass/Astronomy Department Astronomy 114 Lecture 22: Neutron Stars Martin D. Weinberg weinberg@astro.umass.edu UMass/Astronomy Department A114: Lecture 22 02 Apr 2007 Read: Ch. 23,24 Astronomy 114 1/20 Announcements PS#5 due Wednesday

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

CHAPTER 14 II Stellar Evolution

CHAPTER 14 II Stellar Evolution 14-5. Supernova CHAPTER 14 II Stellar Evolution Exactly which stars become supernovae is not yet clear, but more than likely they are massive stars that become highly evolved. A star that develops an iron

More information

Stellar remnants II. Neutron Stars 10/18/2010. (progenitor star 1.4 < M< 3 Msun) Stars, Galaxies & the Universe Announcements

Stellar remnants II. Neutron Stars 10/18/2010. (progenitor star 1.4 < M< 3 Msun) Stars, Galaxies & the Universe Announcements Stars, Galaxies & the Universe Announcements Exam #2 on Wednesday Review sheet and study guide posted by Thursday Use office hours and Astronomy Tutorial hours Covers material since Exam #1 (plus background

More information

Relativity and Black Holes

Relativity and Black Holes Relativity and Black Holes Post-MS Evolution of Very High Mass (>15 M Θ ) Stars similar to high mass except more rapid lives end in Type II supernova explosions main difference: mass of iron core at end

More information

Astronomy 113. Dr. Joseph E. Pesce, Ph.D. Dr. Joseph E. Pesce, Ph.D.

Astronomy 113. Dr. Joseph E. Pesce, Ph.D. Dr. Joseph E. Pesce, Ph.D. Astronomy 113 Dr. Joseph E. Pesce, Ph.D. Stellar Deaths/Endpoints 13-2 Low Mass Stars ³ Like the Sun (< 2 M ) ² Live about 10 billion years (sun is middle aged) ² Create elements through Carbon, Nitrogen,

More information

The Death of Stars. White Dwarfs, Neutron Stars and Black Holes. White Dwarfs

The Death of Stars. White Dwarfs, Neutron Stars and Black Holes. White Dwarfs The Death of Stars White Dwarfs, Neutron Stars and Black Holes White Dwarfs Formed when stars like our Sun reach the end of their life When the Sun s fuel is spent, it will collapse. Don t worry, that

More information

A Star is born: The Sun. SNC1D7-Space

A Star is born: The Sun. SNC1D7-Space 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

More information

Name Date Period. 10. convection zone 11. radiation zone 12. core

Name Date Period. 10. convection zone 11. radiation zone 12. core 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

More information

23 The Death of Stars 1

23 The Death of Stars 1 23 The Death of Stars 1 23.1 Death of Low-Mass Stars W hen last we left off, the star of our show was in dire straits. Life was getting rough, as the star had evolved off the main sequence into a red giant

More information

Astronomy 1 Fall 2016

Astronomy 1 Fall 2016 Astronomy 1 Fall 2016 Lecture 14; November 10, 2016 Previously on Astro 1 Late evolution and death of intermediate-mass stars (about 0.4 M to about 4 M ): red giant when shell hydrogen fusion begins, a

More information

22. Black Holes. Relativistic Length Contraction. Relativistic Time Dilation

22. Black Holes. Relativistic Length Contraction. Relativistic Time Dilation 22. Black Holes Einstein s Special Theory of Relativity Einstein s General Theory of Relativity Black holes exist in some binary star systems Supermassive black holes at of galaxy centers Two properties

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

Neutron Stars, Pulsars, Magnetars, and Black Holes the corpses of high-mass stars

Neutron Stars, Pulsars, Magnetars, and Black Holes the corpses of high-mass stars Neutron Stars, Pulsars, Magnetars, and Black Holes the corpses of high-mass stars Combination X-ray & visible light image of the Crab Nebula Pulsar From Chandra X-ray Observatory and Hubble Space Telescope

More information

Chapter 17 Lecture. The Cosmic Perspective Seventh Edition. Star Stuff Pearson Education, Inc.

Chapter 17 Lecture. The Cosmic Perspective Seventh Edition. Star Stuff Pearson Education, Inc. 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

More information

Termination of Stars

Termination of Stars Termination of Stars Some Quantum Concepts Pauli Exclusion Principle: "Effectively limits the amount of certain kinds of stuff that can be crammed into a given space (particles with personal space ). When

More information

Death of stars is based on. one thing mass.

Death of stars is based on. one thing mass. Death of stars is based on one thing mass. Not the mass they have when born, but the mass they have when they die. Star Death for mass 1.4 solar masses and less. These stars started big 7.5-10 solar masses.

More information

Star formation and Evolution

Star formation and Evolution 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

More information

Test #3 Next Tuesday, Nov. 8 Bring your UNM ID! Bring two number 2 pencils. Announcements. Review for test on Monday, Nov 7 at 3:25pm

Test #3 Next Tuesday, Nov. 8 Bring your UNM ID! Bring two number 2 pencils. Announcements. Review for test on Monday, Nov 7 at 3:25pm Test #3 Next Tuesday, Nov. 8 Bring your UNM ID! Bring two number 2 pencils Announcements Review for test on Monday, Nov 7 at 3:25pm Neutron Star - Black Hole merger Review for Test #3 Nov 8 Topics: Stars

More information

1. (15.1) What are the approximate mass and radius of a white dwarf compared with those of the Sun?

1. (15.1) What are the approximate mass and radius of a white dwarf compared with those of the Sun? SUMMARY White dwarfs, neutron stars, and black holes are the remnants of dead stars. A white dwarf forms when a low mass star expels its outer layers to form a planetary nebula shell and leaves its hot

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

ASTR 101 General Astronomy: Stars & Galaxies. NEXT Tuesday 4/4 MIDTERM #2

ASTR 101 General Astronomy: Stars & Galaxies. NEXT Tuesday 4/4 MIDTERM #2 ASTR 101 General Astronomy: Stars & Galaxies NEXT Tuesday 4/4 MIDTERM #2 The Stellar Graveyard What s In The Stellar Graveyard? Lower mass stars (M< 8M sun ) à white dwarfs Gravity vs. electron degeneracy

More information