The magnitude scale, parallax, the parsec, and Cepheid distances
... • The energy passing through a unit area decreases with the square of d • At distances d1 and d2, the amounts of energy f1 and f2 received by a detector are in the propor;on ...
... • The energy passing through a unit area decreases with the square of d • At distances d1 and d2, the amounts of energy f1 and f2 received by a detector are in the propor;on ...
Chapter 14 Stellar Corpses Stellar Corpses White Dwarfs White
... • If this mass exceeds the maximum allowed for a neutron star (Cygnus X-1 and A0620-00 are two examples), a black hole is currently the only known object that can have high mass and not be visible (and yet its companion is) ...
... • If this mass exceeds the maximum allowed for a neutron star (Cygnus X-1 and A0620-00 are two examples), a black hole is currently the only known object that can have high mass and not be visible (and yet its companion is) ...
The Milky Way and other Galaxies
... M87 = Central, giant elliptical galaxy in the Virgo cluster of galaxies Optical and radio observations detect a jet with velocities up to ~ 1/2 c. ...
... M87 = Central, giant elliptical galaxy in the Virgo cluster of galaxies Optical and radio observations detect a jet with velocities up to ~ 1/2 c. ...
ASTRONOMY 120
... to fuse iron with something else than the reaction releases. This actually decreases the amount of energy available...Nuclear energy generation stops, and as the core collapses under gravity it cannot produce additional energy to stop the collapse. 5. Chaisson Review and Discussion 21.6 What occurs ...
... to fuse iron with something else than the reaction releases. This actually decreases the amount of energy available...Nuclear energy generation stops, and as the core collapses under gravity it cannot produce additional energy to stop the collapse. 5. Chaisson Review and Discussion 21.6 What occurs ...
Supernovae and Gamma-Ray Bursts (draft)
... by this interaction with the circumstellar material. Supernovae (e.g., § 8.3) that show evidence for such interactions are sometimes referred to as Type IIa supernovae (SNe IIa), though how this fits into the overall supernova scheme and, in particular, its relation to SNe IIb devies any obvious log ...
... by this interaction with the circumstellar material. Supernovae (e.g., § 8.3) that show evidence for such interactions are sometimes referred to as Type IIa supernovae (SNe IIa), though how this fits into the overall supernova scheme and, in particular, its relation to SNe IIb devies any obvious log ...
Chapter 26
... • A telescope that collects and amplifies radio waves is a radio telescope. • Because radio waves have long wavelengths, a radio telescope must be built with a very large objective, usually some form of dish antenna. • Astronomers often build several radio telescopes close together and connect th ...
... • A telescope that collects and amplifies radio waves is a radio telescope. • Because radio waves have long wavelengths, a radio telescope must be built with a very large objective, usually some form of dish antenna. • Astronomers often build several radio telescopes close together and connect th ...
Supernovae March 23 − Supernova 1987A
... expelled by giants • Iron was made in massive stars and expelled by supernovae ...
... expelled by giants • Iron was made in massive stars and expelled by supernovae ...
The Milky Way * A Classic Galaxy
... core “central bulge” is made up of very old stars (formed first), the fattened disk stars above and below us are intermediate age (they’ve had time for their originally flat disk orbits to acquire up/down motion by random near-encounters with massive objects), and the youngest stars are closest to t ...
... core “central bulge” is made up of very old stars (formed first), the fattened disk stars above and below us are intermediate age (they’ve had time for their originally flat disk orbits to acquire up/down motion by random near-encounters with massive objects), and the youngest stars are closest to t ...
Black Holes & Quasars—18 Nov • Black hole • Quasar Ast 207 F2009
... material falling into them. • Black holes in center of Milky Way & M87 ...
... material falling into them. • Black holes in center of Milky Way & M87 ...
Pulsar properties - Pulsar Search Collaboratory
... Size of emission region is bounded by the so-called `light cylinder’ - this is an imaginary surface that co-rotates with the neutron star. Einstein asserts the co-rotation speed cannot be greater than the speed of light, c. This sets a fundamental size for the emission region. ...
... Size of emission region is bounded by the so-called `light cylinder’ - this is an imaginary surface that co-rotates with the neutron star. Einstein asserts the co-rotation speed cannot be greater than the speed of light, c. This sets a fundamental size for the emission region. ...
Chapter 8 - TeacherWeb
... Stars can be classified by their size, mass, brightness, color, temperature, spectrum, and age. Can also be classified as main-sequence stars, giants, supergiants, and white dwarfs. Can be reclassified later in its life. http://didyouknow.org/the-size-of-the-sun-in-comparison/ ...
... Stars can be classified by their size, mass, brightness, color, temperature, spectrum, and age. Can also be classified as main-sequence stars, giants, supergiants, and white dwarfs. Can be reclassified later in its life. http://didyouknow.org/the-size-of-the-sun-in-comparison/ ...
Lecture 12: Galaxies View of the Galaxy from within Comparison to
... By plotting the distances of globular clusters (estimated using regular variable stars) we can determine the sun’s location relative to the stellar halo of the Galaxy. We conclude that our Sun lies within the galactic disk, some 8000 pc (26,000 ly) from the Galactic centre. ...
... By plotting the distances of globular clusters (estimated using regular variable stars) we can determine the sun’s location relative to the stellar halo of the Galaxy. We conclude that our Sun lies within the galactic disk, some 8000 pc (26,000 ly) from the Galactic centre. ...
chapter 26 instructor notes
... While the Eggen, Lynden-Bell, and Sandage mechanism has been proposed for the formation of disk galaxies like spirals and lenticulars, the formation of ellipticals has generally been considered to have been a faster process in which star formation was extremely efficient, leaving nothing for the cre ...
... While the Eggen, Lynden-Bell, and Sandage mechanism has been proposed for the formation of disk galaxies like spirals and lenticulars, the formation of ellipticals has generally been considered to have been a faster process in which star formation was extremely efficient, leaving nothing for the cre ...
TF_final3 - Arecibo Observatory
... velocity width (W) of the lines is proportional to its luminosity (L) following an equation, L ∝ In a sample of 33 LIRGs the neutral hydrogen emission line width was measured. The luminosities of these galaxies from literature were found and a study was made of whether the Tully-Fisher law is mainta ...
... velocity width (W) of the lines is proportional to its luminosity (L) following an equation, L ∝ In a sample of 33 LIRGs the neutral hydrogen emission line width was measured. The luminosities of these galaxies from literature were found and a study was made of whether the Tully-Fisher law is mainta ...
CosmologyL1
... So we are seeing this part of the universe not as it looks now, but as it looked as many as 12 billion years ago. ...
... So we are seeing this part of the universe not as it looks now, but as it looked as many as 12 billion years ago. ...
The Milky Way galaxy
... What could this dark matter be? Relic particles from the Big Bang? Lots of 3 solar mass black holes? This is one of the biggest mysteries in modern astronomy. ...
... What could this dark matter be? Relic particles from the Big Bang? Lots of 3 solar mass black holes? This is one of the biggest mysteries in modern astronomy. ...
Word doc - UC-HiPACC - University of California, Santa Cruz
... Supernovae are not alike. For decades, astronomers had known that supernovae fell into different types based on their light curves, that is, their pattern of rising and falling brightness. Later, they found these types actually corresponded to different physical circumstances triggering the explosio ...
... Supernovae are not alike. For decades, astronomers had known that supernovae fell into different types based on their light curves, that is, their pattern of rising and falling brightness. Later, they found these types actually corresponded to different physical circumstances triggering the explosio ...
Black Hole in M83 - Astronomical Society of the Pacific
... to X-ray temperatures while in the process of being swallowed up. • In this new case, there was no blue source present before the outburst, and so no hot, blue star. So what is the blue source and where did it come from? ...
... to X-ray temperatures while in the process of being swallowed up. • In this new case, there was no blue source present before the outburst, and so no hot, blue star. So what is the blue source and where did it come from? ...
Lecture 10: The Milky Way
... We live in a galaxy that has three major components of different ages and metallicities. Disc (thin+thick) – about 25kpc in radius, only about 1kpc thick. Most of the stars are young (0-8 Gyr), and have about the same metal content as the Sun. Total stellar mass of about 6x1010M. Bulge – a mostly o ...
... We live in a galaxy that has three major components of different ages and metallicities. Disc (thin+thick) – about 25kpc in radius, only about 1kpc thick. Most of the stars are young (0-8 Gyr), and have about the same metal content as the Sun. Total stellar mass of about 6x1010M. Bulge – a mostly o ...
Galaxies and Cosmology
... Hubble’s Law tells us that all galaxies are moving apart at a rate proportional to their separation distance The slope of this relationship is called Hubble’s Constant, or H0 If that rate stayed the same throughout the history of the universe, we could run a “movie” of the universe backwards to find ...
... Hubble’s Law tells us that all galaxies are moving apart at a rate proportional to their separation distance The slope of this relationship is called Hubble’s Constant, or H0 If that rate stayed the same throughout the history of the universe, we could run a “movie” of the universe backwards to find ...
runaway - Astronomy & Astrophysics Group
... The galaxy is, in fact, nothing but a collection of innumerable stars grouped together in clusters. Upon whatever part of it the telescope is directed, a vast crowd of stars is immediately presented to view. Many of them are rather large and quite bright, while the number of smaller ones is quite be ...
... The galaxy is, in fact, nothing but a collection of innumerable stars grouped together in clusters. Upon whatever part of it the telescope is directed, a vast crowd of stars is immediately presented to view. Many of them are rather large and quite bright, while the number of smaller ones is quite be ...
Chapter 13
... 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. ...
... 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. ...
1:45 PM TuTh This is a one-quarter course on
... Physical Sciences 130; 12 - 1:45 PM TuTh This is a one-quarter course on stars, stellar evolution, and topics known collectively as ``high energy astrophysics'' as it applies to stellar phenomena. Thus the subject matter includes, in addition to the study of the stars themselves - their observed pro ...
... Physical Sciences 130; 12 - 1:45 PM TuTh This is a one-quarter course on stars, stellar evolution, and topics known collectively as ``high energy astrophysics'' as it applies to stellar phenomena. Thus the subject matter includes, in addition to the study of the stars themselves - their observed pro ...
Gamma-ray burst
Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several hours. The initial burst is usually followed by a longer-lived ""afterglow"" emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).Most observed GRBs are believed to consist of a narrow beam of intense radiation released during a supernova or hypernova as a rapidly rotating, high-mass star collapses to form a neutron star, quark star, or black hole. A subclass of GRBs (the ""short"" bursts) appear to originate from a different process – this may be due to the merger of binary neutron stars. The cause of the precursor burst observed in some of these short events may be due to the development of a resonance between the crust and core of such stars as a result of the massive tidal forces experienced in the seconds leading up to their collision, causing the entire crust of the star to shatter.The sources of most GRBs are billions of light years away from Earth, implying that the explosions are both extremely energetic (a typical burst releases as much energy in a few seconds as the Sun will in its entire 10-billion-year lifetime) and extremely rare (a few per galaxy per million years). All observed GRBs have originated from outside the Milky Way galaxy, although a related class of phenomena, soft gamma repeater flares, are associated with magnetars within the Milky Way. It has been hypothesized that a gamma-ray burst in the Milky Way, pointing directly towards the Earth, could cause a mass extinction event.GRBs were first detected in 1967 by the Vela satellites, a series of satellites designed to detect covert nuclear weapons tests. Hundreds of theoretical models were proposed to explain these bursts in the years following their discovery, such as collisions between comets and neutron stars. Little information was available to verify these models until the 1997 detection of the first X-ray and optical afterglows and direct measurement of their redshifts using optical spectroscopy, and thus their distances and energy outputs. These discoveries, and subsequent studies of the galaxies and supernovae associated with the bursts, clarified the distance and luminosity of GRBs. These facts definitively placed them in distant galaxies and also connected long GRBs with the explosion of massive stars, the only possible source for the energy outputs observed.