Today in Astronomy 102: electron degeneracy pressure and white
... The planetary nebula’s material expands away from the scene in a few thousand years, leaving behind the hot, former core of the star, now about the size of Earth. Its weight supported against further collapse by electron degeneracy pressure, it will do nothing but sit there and cool off, for eternit ...
... The planetary nebula’s material expands away from the scene in a few thousand years, leaving behind the hot, former core of the star, now about the size of Earth. Its weight supported against further collapse by electron degeneracy pressure, it will do nothing but sit there and cool off, for eternit ...
Early Star-Forming Galaxies
... 9 billion to 11 billion years ago. Scientists would particularly like to know whether a quasi-steady, long-lasting process in isolated galaxies or a more rapid, starburst mode in large, merging galaxies increased the production of stars. Recent findings from a study using Hubble and the European Sp ...
... 9 billion to 11 billion years ago. Scientists would particularly like to know whether a quasi-steady, long-lasting process in isolated galaxies or a more rapid, starburst mode in large, merging galaxies increased the production of stars. Recent findings from a study using Hubble and the European Sp ...
The Sun and other Stars
... of mass to generate a large quantity of energy. This lead the way for two astrophysicists to determine that the Sun was powered by the fusion of Hydrogen ...
... of mass to generate a large quantity of energy. This lead the way for two astrophysicists to determine that the Sun was powered by the fusion of Hydrogen ...
PPS
... A parameter which determines the size of regions in a cloud of gas with a certain temperature and density that are liable to gravitational collapse. The Jeans' criterion is only an approximate guide, but it predicts that, for example, the size of the objects formed by gravitational collapse at the t ...
... A parameter which determines the size of regions in a cloud of gas with a certain temperature and density that are liable to gravitational collapse. The Jeans' criterion is only an approximate guide, but it predicts that, for example, the size of the objects formed by gravitational collapse at the t ...
STUDY GUIDE:
... it stays together due to the forces of its own gravitation. The hotter a star’s core, or center, the more reactions it produces. A star’s gravity depends upon the mass of the materials inside its core. Most stars are composed primarily of hydrogen. The rest of a star’s content is helium. In the core ...
... it stays together due to the forces of its own gravitation. The hotter a star’s core, or center, the more reactions it produces. A star’s gravity depends upon the mass of the materials inside its core. Most stars are composed primarily of hydrogen. The rest of a star’s content is helium. In the core ...
Document
... Synchrotron and inverse Compton radaition emitted by ultra –relativistic flow of electron-positron plasma along the axis of the distant rotating super-massive black ...
... Synchrotron and inverse Compton radaition emitted by ultra –relativistic flow of electron-positron plasma along the axis of the distant rotating super-massive black ...
Chapter 6 Stars
... are the remains of high-mass stars. They are even smaller and denser than white dwarfs. A neutron star may contain as much as three times the mass of the sun but be only about 25 kilometers in diameter, the size of a city! In 1967, Jocelyn Bell, a British astronomy student, detected an object in spa ...
... are the remains of high-mass stars. They are even smaller and denser than white dwarfs. A neutron star may contain as much as three times the mass of the sun but be only about 25 kilometers in diameter, the size of a city! In 1967, Jocelyn Bell, a British astronomy student, detected an object in spa ...
4P38.pdf
... The results from the “Sun in Time” program suggest that the coronal X-ray-EUV emissions of the young main-sequence Sun were ~100-1000 times stronger than those of the present Sun. Similarly, the transition region and chromospheric FUV-UV emissions of the young Sun are expected to be 20-60 and 10-20 ...
... The results from the “Sun in Time” program suggest that the coronal X-ray-EUV emissions of the young main-sequence Sun were ~100-1000 times stronger than those of the present Sun. Similarly, the transition region and chromospheric FUV-UV emissions of the young Sun are expected to be 20-60 and 10-20 ...
The Montreal White Dwarf Database: a Tool for the Community
... community will be to add the possibility to make luminosity functions and filter with S/N ratio, wavelength range coverage and resolution of the spectroscopic observations. A comment section to discuss individual object or general topics will also be implemented. We also plan to include our own resu ...
... community will be to add the possibility to make luminosity functions and filter with S/N ratio, wavelength range coverage and resolution of the spectroscopic observations. A comment section to discuss individual object or general topics will also be implemented. We also plan to include our own resu ...
Reading Earth in Space
... - who was inside the spacecraft? * The first woman in space. * A spaceship was launched to orbit the Earth and it didn’t return. * The first person to set foot on the Moon. * The first human being in space. * The first person to “walk” in space. ...
... - who was inside the spacecraft? * The first woman in space. * A spaceship was launched to orbit the Earth and it didn’t return. * The first person to set foot on the Moon. * The first human being in space. * The first person to “walk” in space. ...
luminosities
... • How do scientists accumulate and use data? With this chapter you leave our sun behind and begin your study of the billions of stars that dot the sky. In a sense, the star is the basic building block of the universe. If you hope to understand what the universe is and how it works, you must understa ...
... • How do scientists accumulate and use data? With this chapter you leave our sun behind and begin your study of the billions of stars that dot the sky. In a sense, the star is the basic building block of the universe. If you hope to understand what the universe is and how it works, you must understa ...
The woman who dissected the Sun
... Applying the methods of Fowler and Milne, Payne found that Cannon's sequence was actually a temperature sequence, with O the hottest and S the coolest. It was temperature not composition that was responsible for the most of the differences between stars. Just because a star's spectrum showed no lig ...
... Applying the methods of Fowler and Milne, Payne found that Cannon's sequence was actually a temperature sequence, with O the hottest and S the coolest. It was temperature not composition that was responsible for the most of the differences between stars. Just because a star's spectrum showed no lig ...
Power-point slides for Lecture 5
... then b) capture electrons on free protons; and c) collapse to nuclear density as a free neutron gas as some texts naively describe. Bound nuclei persist, then finally touch and melt into one gigantic nucleus with 1057 nucleons – the neutron star. Ye declines to about 0.37 before the core becomes opa ...
... then b) capture electrons on free protons; and c) collapse to nuclear density as a free neutron gas as some texts naively describe. Bound nuclei persist, then finally touch and melt into one gigantic nucleus with 1057 nucleons – the neutron star. Ye declines to about 0.37 before the core becomes opa ...
Diapositiva 1
... The spectra of two nebulous objects near NGC 1999 (ApJ 113, 697). On a series of direct photographs taken with the Crosslyer reflector in 1946 and 1947 and centered on the diffuse nebula NGC 1999, there appear several peculiar nebulous objects. The brightest of these (referred to hereafter as "No. 1 ...
... The spectra of two nebulous objects near NGC 1999 (ApJ 113, 697). On a series of direct photographs taken with the Crosslyer reflector in 1946 and 1947 and centered on the diffuse nebula NGC 1999, there appear several peculiar nebulous objects. The brightest of these (referred to hereafter as "No. 1 ...
Chapter 20 Notes (smaller PDF file)
... • A high-mass star dies in a violent cataclysm in which its core collapses and most of its matter is ejected into space at high speeds • The luminosity of the star increases suddenly by a factor of around 108 during this explosion, producing a supernova • The matter ejected from the supernova, movin ...
... • A high-mass star dies in a violent cataclysm in which its core collapses and most of its matter is ejected into space at high speeds • The luminosity of the star increases suddenly by a factor of around 108 during this explosion, producing a supernova • The matter ejected from the supernova, movin ...
large PDF file
... • A high-mass star dies in a violent cataclysm in which its core collapses and most of its matter is ejected into space at high speeds • The luminosity of the star increases suddenly by a factor of around 108 during this explosion, producing a supernova • The matter ejected from the supernova, movin ...
... • A high-mass star dies in a violent cataclysm in which its core collapses and most of its matter is ejected into space at high speeds • The luminosity of the star increases suddenly by a factor of around 108 during this explosion, producing a supernova • The matter ejected from the supernova, movin ...
The Formation of Stars and Solar Systems
... Giant Molecular Clouds • Some parts of space, however, are not wide open frontiers containing a few atoms. These cosmic spaces comprise dense clouds of dust and gas left over from galaxy formation. • Since these clouds are cooler than most places, they are perfect breeding grounds for star birth. W ...
... Giant Molecular Clouds • Some parts of space, however, are not wide open frontiers containing a few atoms. These cosmic spaces comprise dense clouds of dust and gas left over from galaxy formation. • Since these clouds are cooler than most places, they are perfect breeding grounds for star birth. W ...
ph507-16-4form
... Massive Stars & Clusters: Massive stars should not form: hydrogen burning begins while accreting: radiation pressure should resist the infall. Accretion must be high and through a disk: to suffocate the feedback. Massive stars create hot molecular cores, masers, compact/extended H II ...
... Massive Stars & Clusters: Massive stars should not form: hydrogen burning begins while accreting: radiation pressure should resist the infall. Accretion must be high and through a disk: to suffocate the feedback. Massive stars create hot molecular cores, masers, compact/extended H II ...
The Interstellar Medium Chapter 10
... 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 in the interstellar medium because a) dense interstellar clouds are the birth place of stars b) Dark clouds alter and absorb the l ...
... 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 in the interstellar medium because a) dense interstellar clouds are the birth place of stars b) Dark clouds alter and absorb the l ...
18. Formation of Stars.
... • The evolution of a protostar can be followed on the H-R diagram. The early protostar is relatively cool and low luminosity. So, the star first appears on the extreme lower right portion of the H-R diagram. • The protostar's initial free-fall contraction is slowed by the increasing density a ...
... • The evolution of a protostar can be followed on the H-R diagram. The early protostar is relatively cool and low luminosity. So, the star first appears on the extreme lower right portion of the H-R diagram. • The protostar's initial free-fall contraction is slowed by the increasing density a ...