Stellar evolution, II
... form heavier atoms would use up more energy than they would produce. The outer layers squeeze down onto the iron core and the star explodes as a Type II supernova. ...
... form heavier atoms would use up more energy than they would produce. The outer layers squeeze down onto the iron core and the star explodes as a Type II supernova. ...
–1– 1. The Luminosity of Protostars We derived in the previous
... (From 5.2 in Hartmann, a very good read on this topic). In reality, a protostar is not one optically thick shell, but a series of concentric shells with decreasing density. At a given wavelength, most of radiation can be considered to come from the τ = 2/3 surface, just as in stellar photospheres (E ...
... (From 5.2 in Hartmann, a very good read on this topic). In reality, a protostar is not one optically thick shell, but a series of concentric shells with decreasing density. At a given wavelength, most of radiation can be considered to come from the τ = 2/3 surface, just as in stellar photospheres (E ...
PowerPoint
... Q: Does anything survive the Type II SN Explosion? 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 re ...
... Q: Does anything survive the Type II SN Explosion? 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 re ...
The Hidden Lives of Galaxies NSTA 2001
... • Under collapse, protons and electrons combine to form neutrons. • 10 Km across Black Hole (If mass of core > 5 x Solar) • Not even compacted neutrons can support weight of very massive stars. ...
... • Under collapse, protons and electrons combine to form neutrons. • 10 Km across Black Hole (If mass of core > 5 x Solar) • Not even compacted neutrons can support weight of very massive stars. ...
PHYS 2410 General Astronomy Homework 5
... 18. Which of the stars in the diagram above has the brightest absolute visual magnitude? ...
... 18. Which of the stars in the diagram above has the brightest absolute visual magnitude? ...
Lecture 13 - Main Sequence Stars
... • Spheres of water have several properties: mass, volume, radius, surface area … • We can make a “Vogt-Russell” theorem for balls of water that says that all of the other properties of a ball of water are determined by just the mass and even write down equations, i.e. volume = mass/(density of water ...
... • Spheres of water have several properties: mass, volume, radius, surface area … • We can make a “Vogt-Russell” theorem for balls of water that says that all of the other properties of a ball of water are determined by just the mass and even write down equations, i.e. volume = mass/(density of water ...
PPT - Yale University
... Black hole growth by gas accretion Standard accretion disks become inefficient and unstable at radii > 0.1 pc, so if gas is to get into such a region from a galactic bulge, its angular momentum must be reduced by at least 3 orders of magnitude in some other way. ...
... Black hole growth by gas accretion Standard accretion disks become inefficient and unstable at radii > 0.1 pc, so if gas is to get into such a region from a galactic bulge, its angular momentum must be reduced by at least 3 orders of magnitude in some other way. ...
Astronomy
... sizes and their color range from blue to red. The size of a star depends on the gas and dust that have been collected during the birth of the star. The color of the star depends on the surface temperature of the star. The more mass a star starts out with the hotter and brighter it will be. ...
... sizes and their color range from blue to red. The size of a star depends on the gas and dust that have been collected during the birth of the star. The color of the star depends on the surface temperature of the star. The more mass a star starts out with the hotter and brighter it will be. ...
MULTIPLE CHOICE QUESTIONS (50 pts
... D. both of them have very small masses compared to the Earth. E. the wind speeds are very high and produce a blue shift. 4. The single most important factor influencing a star’s evolution is A. the strength of its magnetic field. B. its rotation rate. C. its surface temperature. D. its mass. E. its ...
... D. both of them have very small masses compared to the Earth. E. the wind speeds are very high and produce a blue shift. 4. The single most important factor influencing a star’s evolution is A. the strength of its magnetic field. B. its rotation rate. C. its surface temperature. D. its mass. E. its ...
downloadable pdf - University of Florida
... A University of Florida-led team of astronomers may have discovered the brightest star yet observed in the universe, a fiery behemoth that could be as much as seven times brighter than the current record holder. But don’t expect to find the star — which is at least 5 million times brighter than the ...
... A University of Florida-led team of astronomers may have discovered the brightest star yet observed in the universe, a fiery behemoth that could be as much as seven times brighter than the current record holder. But don’t expect to find the star — which is at least 5 million times brighter than the ...
8.4 White Dwarfs
... Loose protons and electrons near the surface of the neutron star will be sweep up and stream along the magnetic field lines towards the north and south magnetic poles of the neutron star. The magnetic axis of the neutron star does not necessarily have to be aligned with the rotation axis (like the ...
... Loose protons and electrons near the surface of the neutron star will be sweep up and stream along the magnetic field lines towards the north and south magnetic poles of the neutron star. The magnetic axis of the neutron star does not necessarily have to be aligned with the rotation axis (like the ...
File
... •A star is a huge ball of hot glowing gases, called plasma. •Stars twinkle because the light is distorted by Earth’s atmosphere. •All stars have one thing in common, the way they produce energy. •The energy comes from nuclear reactions that change hydrogen into helium. It is as if millions of atomi ...
... •A star is a huge ball of hot glowing gases, called plasma. •Stars twinkle because the light is distorted by Earth’s atmosphere. •All stars have one thing in common, the way they produce energy. •The energy comes from nuclear reactions that change hydrogen into helium. It is as if millions of atomi ...
Scientists classify stars by
... would look the same because the two lights are exactly the same. Their absolute magnitude is the same. Distance makes them look different. The same is true for stars. Two stars could be the same brightness but their distance from us makes their brightness different. ...
... would look the same because the two lights are exactly the same. Their absolute magnitude is the same. Distance makes them look different. The same is true for stars. Two stars could be the same brightness but their distance from us makes their brightness different. ...
I`m using this stupid huge font
... Stellar scattering changes the structure of the galaxy over time Spiral disk becomes extended and diffuse Most stars are lost, but a few fall to center ...
... Stellar scattering changes the structure of the galaxy over time Spiral disk becomes extended and diffuse Most stars are lost, but a few fall to center ...
doc - EU-HOU
... You will fit your measurements by hand. In order to do this, iteratively change the 3 parameters W, T and Phi ( checking the fit (the red points and curve superimposed on the blue points) by eye after each iteration. It is also possible to find the best fit by minimising the “solver” value1 displ ...
... You will fit your measurements by hand. In order to do this, iteratively change the 3 parameters W, T and Phi ( checking the fit (the red points and curve superimposed on the blue points) by eye after each iteration. It is also possible to find the best fit by minimising the “solver” value1 displ ...
solutions - Las Cumbres Observatory
... 2. How are the compositions of the two stars changing over their life times? T he larger star uses more of its fuel and its mass goes down visibly on the graph. The 1 solar mass star appears to lose very little ...
... 2. How are the compositions of the two stars changing over their life times? T he larger star uses more of its fuel and its mass goes down visibly on the graph. The 1 solar mass star appears to lose very little ...
solution
... The gravitational energy causes Kelvin-Helmholtz contraction, which increases the pressure, density and temperature of the central region of a protostar. Once the temperature exceeds a few million K, H begins to fuse into He (via the p-p chain in a Sun-sized protostar, or the CNO cycle in a larger o ...
... The gravitational energy causes Kelvin-Helmholtz contraction, which increases the pressure, density and temperature of the central region of a protostar. Once the temperature exceeds a few million K, H begins to fuse into He (via the p-p chain in a Sun-sized protostar, or the CNO cycle in a larger o ...
Presentation available here - Lunar and Planetary Institute
... All core collapse explosions are asymmetric, maybe produced by magnetic jets. How can this be proved? Gamma-ray bursts are caused by jets of material moving at nearly the speed of light. Do they mark the birth of black holes? At least some gamma-ray bursts (and maybe all) arise in supernova ex ...
... All core collapse explosions are asymmetric, maybe produced by magnetic jets. How can this be proved? Gamma-ray bursts are caused by jets of material moving at nearly the speed of light. Do they mark the birth of black holes? At least some gamma-ray bursts (and maybe all) arise in supernova ex ...
Document
... ii. A region of condensing matter will begin to heat up and start to glow forming Protostars. If a protostar contains enough matter the central temperature reaches 15 million degrees centigrade. iii. At this temperature, nuclear reactions in which hydrogen fuses to form helium can start. iv. The sta ...
... ii. A region of condensing matter will begin to heat up and start to glow forming Protostars. If a protostar contains enough matter the central temperature reaches 15 million degrees centigrade. iii. At this temperature, nuclear reactions in which hydrogen fuses to form helium can start. iv. The sta ...
Epsilon Auriage: 200 Years of Astronomical History
... A swarm of meteorites, 10-100 um in diameter. ...
... A swarm of meteorites, 10-100 um in diameter. ...
Hungry Young Stars: A New Explanation for the FU Ori Outbursts
... • We provide an explanation for the origin of FU Ori bursts. • A young star devours embryos that form in the disk, resulting in colossal bursts of luminosity. This process repeats as long as nebular material rains onto the disk. • The new feature in our model is the self-consistent formation and evo ...
... • We provide an explanation for the origin of FU Ori bursts. • A young star devours embryos that form in the disk, resulting in colossal bursts of luminosity. This process repeats as long as nebular material rains onto the disk. • The new feature in our model is the self-consistent formation and evo ...
Stellar evolution, II
... mass of Sun = 2 X 1030 kg 0.007 of mass of hydrogen is converted into energy 0.1 of mass of Sun (the core) is converted in He Total energy liberated by Sun during main sequence phase is (2 X 1030) X 0.007 X 0.1 X c2 = 1.26 X 1044 J. Luminosity of Sun = 3.8 X 1026 Joules/sec ...
... mass of Sun = 2 X 1030 kg 0.007 of mass of hydrogen is converted into energy 0.1 of mass of Sun (the core) is converted in He Total energy liberated by Sun during main sequence phase is (2 X 1030) X 0.007 X 0.1 X c2 = 1.26 X 1044 J. Luminosity of Sun = 3.8 X 1026 Joules/sec ...
Sky Notes - April 2012 - North Devon Astronomical Society
... the orbital motion of a smaller or less powerful companion, the variability in Cepheids is due to the pulsation of the star itself. In the case of Delta Cephei, the star’s brightness ranges between magnitude +3.5 and +4.4 and occurs over a period of around five and a half days. Cepheids are importan ...
... the orbital motion of a smaller or less powerful companion, the variability in Cepheids is due to the pulsation of the star itself. In the case of Delta Cephei, the star’s brightness ranges between magnitude +3.5 and +4.4 and occurs over a period of around five and a half days. Cepheids are importan ...
Answer all questions in Section A and two and only two questions in
... explained by the black-body radiation of the component stars. Describe the process that provides the energy for this radiation in interacting binaries. Discuss the relative efficiency of this process for white dwarfs, neutron stars and black holes. ...
... explained by the black-body radiation of the component stars. Describe the process that provides the energy for this radiation in interacting binaries. Discuss the relative efficiency of this process for white dwarfs, neutron stars and black holes. ...
Cygnus X-1
Cygnus X-1 (abbreviated Cyg X-1) is a well-known galactic X-ray source, thought to be a black hole, in the constellation Cygnus. It was discovered in 1964 during a rocket flight and is one of the strongest X-ray sources seen from Earth, producing a peak X-ray flux density of 6977229999999999999♠2.3×10−23 Wm−2 Hz−1 (7003230000000000000♠2.3×103 Jansky). Cygnus X-1 was the first X-ray source widely accepted to be a black hole and it remains among the most studied astronomical objects in its class. The compact object is now estimated to have a mass about 14.8 times the mass of the Sun and has been shown to be too small to be any known kind of normal star, or other likely object besides a black hole. If so, the radius of its event horizon is about 7004440000000000000♠44 km.Cygnus X-1 belongs to a high-mass X-ray binary system about 7019574266339685654♠6070 ly from the Sun that includes a blue supergiant variable star designated HDE 226868 which it orbits at about 0.2 AU, or 20% of the distance from the Earth to the Sun. A stellar wind from the star provides material for an accretion disk around the X-ray source. Matter in the inner disk is heated to millions of degrees, generating the observed X-rays. A pair of jets, arranged perpendicular to the disk, are carrying part of the energy of the infalling material away into interstellar space.This system may belong to a stellar association called Cygnus OB3, which would mean that Cygnus X-1 is about five million years old and formed from a progenitor star that had more than 7001400000000000000♠40 solar masses. The majority of the star's mass was shed, most likely as a stellar wind. If this star had then exploded as a supernova, the resulting force would most likely have ejected the remnant from the system. Hence the star may have instead collapsed directly into a black hole.Cygnus X-1 was the subject of a friendly scientific wager between physicists Stephen Hawking and Kip Thorne in 1975, with Hawking betting that it was not a black hole. He conceded the bet in 1990 after observational data had strengthened the case that there was indeed a black hole in the system. This hypothesis has not been confirmed due to a lack of direct observation but has generally been accepted from indirect evidence.