The Cosmic Cupboard
... be the next most common, butof I’d rather just present results and let you see that nature has thethe Elements made or job of understanding what goes into making a planet a bit simpler that we may have though. ...
... be the next most common, butof I’d rather just present results and let you see that nature has thethe Elements made or job of understanding what goes into making a planet a bit simpler that we may have though. ...
Lyman-α: The Many Applications and Challenges of This Powerful
... studying stellar mass loss, fluorescent excitation of molecular hydrogen in the environments of very young stars, the deuterium/hydrogen ratio in the Galaxy, and mass loss and photochemical processes in exoplanet atmospheres. These powerful applications result from Lyman-α being the strongest emissi ...
... studying stellar mass loss, fluorescent excitation of molecular hydrogen in the environments of very young stars, the deuterium/hydrogen ratio in the Galaxy, and mass loss and photochemical processes in exoplanet atmospheres. These powerful applications result from Lyman-α being the strongest emissi ...
The Age and Progenitor Mass of Sirius B
... usual practice in the published analyses of the cluster white dwarfs is, as stated previously, to use Wood’s calculations with the same mixture. Other available calculations from Wood are for pure carbon and for pure oxygen compositions. The 5 M⊙ sequence calculated from TYCHO produces very nearly a ...
... usual practice in the published analyses of the cluster white dwarfs is, as stated previously, to use Wood’s calculations with the same mixture. Other available calculations from Wood are for pure carbon and for pure oxygen compositions. The 5 M⊙ sequence calculated from TYCHO produces very nearly a ...
Chapter 10
... Once many stars are plotted on an H–R diagram, a pattern begins to form: These are the 80 closest stars to us; note the dashed lines of constant radius. ...
... Once many stars are plotted on an H–R diagram, a pattern begins to form: These are the 80 closest stars to us; note the dashed lines of constant radius. ...
3D GR Hydrodynamic Simulations of Binary Neutron Star
... Shock front moving from fine to coarse grid ...
... Shock front moving from fine to coarse grid ...
W > 1 - The Open University
... NGC1502 (5.7) oc. A fine open cluster. Extending NW of this cluster is a line of 9th and 10th magnitude stars which form "Kemble's Cascade". A beautiful sight in binoculars or a low power wide-field eyepiece on small telescopes. NGC2403 (8.4) sg. Visible in large binoculars. It lies at a distance of ...
... NGC1502 (5.7) oc. A fine open cluster. Extending NW of this cluster is a line of 9th and 10th magnitude stars which form "Kemble's Cascade". A beautiful sight in binoculars or a low power wide-field eyepiece on small telescopes. NGC2403 (8.4) sg. Visible in large binoculars. It lies at a distance of ...
Mass segregation in star clusters is not energy equipartition
... that the formation of a sub-system of the most massive stars in the core leads to the suppression of energy equipartition in clusters. Our initial conditions, which contain spatial and kinematic substructure, are informed by observations of young star-forming regions and lead to mass segregation and ...
... that the formation of a sub-system of the most massive stars in the core leads to the suppression of energy equipartition in clusters. Our initial conditions, which contain spatial and kinematic substructure, are informed by observations of young star-forming regions and lead to mass segregation and ...
A new class of rapidly pulsating star
... In Paper I of this series (Kilkenny et al. 1997), a new class of rapidly pulsating sdB stars, the EC 14026 stars, was announced. To date, more than half a dozen of these stars have been discovered. Observations of four of these are now sufficient for publication (Kilkenny et al. 1997; O'Donoghue et ...
... In Paper I of this series (Kilkenny et al. 1997), a new class of rapidly pulsating sdB stars, the EC 14026 stars, was announced. To date, more than half a dozen of these stars have been discovered. Observations of four of these are now sufficient for publication (Kilkenny et al. 1997; O'Donoghue et ...
PRS Questions (queestions after Midterm 2)
... the Sun than the Earth. How much lower is the flux of Sunlight at Uranus compared to the flux at the Earth? ...
... the Sun than the Earth. How much lower is the flux of Sunlight at Uranus compared to the flux at the Earth? ...
The Milky Way
... How can we measure the mass of the Milky Way? Why do stars behind dust clouds appear red? Why is the sky blue? Why are wavelengths of light outside the visible useful in studying the Milky Way? • How is the 21 cm line of Hydrogen produced? • Describe the spiral arms of the Milky Way and what ...
... How can we measure the mass of the Milky Way? Why do stars behind dust clouds appear red? Why is the sky blue? Why are wavelengths of light outside the visible useful in studying the Milky Way? • How is the 21 cm line of Hydrogen produced? • Describe the spiral arms of the Milky Way and what ...
Quantum effects in astrophysics
... levels of ordinary hydrogen by about one part in 2mP / me 3700 . In the visible part of the spectrum, this corresponds to a line shift on the order of 1.5 angstroms. This shift could be easily detected, yet, for many years, no deuterium was ever detected in any astronomical object. In contrast, th ...
... levels of ordinary hydrogen by about one part in 2mP / me 3700 . In the visible part of the spectrum, this corresponds to a line shift on the order of 1.5 angstroms. This shift could be easily detected, yet, for many years, no deuterium was ever detected in any astronomical object. In contrast, th ...
Central Massive Objects: The Stellar Nuclei – Black Hole
... signatures for intermediate mass black holes (IMBHs) in globular clusters. Clearly, the most compelling evidence is the detection of non-thermal emission, seen, for example, for G1 in M31, but globular clusters have very little or even no gas and so the emission is very faint or absent. The evidence ...
... signatures for intermediate mass black holes (IMBHs) in globular clusters. Clearly, the most compelling evidence is the detection of non-thermal emission, seen, for example, for G1 in M31, but globular clusters have very little or even no gas and so the emission is very faint or absent. The evidence ...
Living alongside Monsters: Matter around Central Massive Black Holes Q. Daniel Wang
... 39’ (300 light-year) • Distance to the Galactic center: 26,000 light-year • Resolution: 0.025 light-year (0.2”) • 144 HST orbits, taken between Feb and June, 2008 144X4X4=2304 images for each of the two wavelength filters ...
... 39’ (300 light-year) • Distance to the Galactic center: 26,000 light-year • Resolution: 0.025 light-year (0.2”) • 144 HST orbits, taken between Feb and June, 2008 144X4X4=2304 images for each of the two wavelength filters ...
10.00 points 10.00 points 10.00 points 10.00 points 10.00 points
... Although the Sun's core has a density much greater than rock it is considered a gaseous object because The Sun's high internal temperatures prevent the atoms from bonding together to form a liquid or a solid. A large fraction of the Sun's interior is made of electromagnetic radiation (light). It is ...
... Although the Sun's core has a density much greater than rock it is considered a gaseous object because The Sun's high internal temperatures prevent the atoms from bonding together to form a liquid or a solid. A large fraction of the Sun's interior is made of electromagnetic radiation (light). It is ...
Slides from the fourth lecture
... Associated with explosions of Massive stars Their underlying continuum is smooth power law ...
... Associated with explosions of Massive stars Their underlying continuum is smooth power law ...
Positive And Negative Time Scaling And Time Portal
... Radius of this Circle must be proportional to the Space and/ or Time Potential Delta through which we wish to launch ourselves. The Lightning Circle should be made of Nuclear Reactions Field which again should be a Recursion Scheme of Time of our Sun and/ or any Star, or a Galaxy and/ or a Universe. ...
... Radius of this Circle must be proportional to the Space and/ or Time Potential Delta through which we wish to launch ourselves. The Lightning Circle should be made of Nuclear Reactions Field which again should be a Recursion Scheme of Time of our Sun and/ or any Star, or a Galaxy and/ or a Universe. ...
Power Point Presentation
... where they burn hydrogen in nuclear reactions in their cores Burning rate is higher for more massive stars - hence their lifetimes on the main sequence are much shorter and they are rather rare Red dwarf stars are the most common as they burn hydrogen slowly and live the longest Often called dwarfs ...
... where they burn hydrogen in nuclear reactions in their cores Burning rate is higher for more massive stars - hence their lifetimes on the main sequence are much shorter and they are rather rare Red dwarf stars are the most common as they burn hydrogen slowly and live the longest Often called dwarfs ...
Document
... wide variety of systems, from an ideal gas to a cluster of galaxies to a star in equilibrium! ...
... wide variety of systems, from an ideal gas to a cluster of galaxies to a star in equilibrium! ...
featured in the Arizona Daily Star
... piece of stardust. By comparing the stardust grain’s composition to theoretical predictions, we can infer the kind of star the grain came from, its mass, its evolutionary state, and its bulk chemical makeup. Once we know the meteorite contains stardust, we probe deeper. Using a focused-ionbeam scann ...
... piece of stardust. By comparing the stardust grain’s composition to theoretical predictions, we can infer the kind of star the grain came from, its mass, its evolutionary state, and its bulk chemical makeup. Once we know the meteorite contains stardust, we probe deeper. Using a focused-ionbeam scann ...
Stellar Evolution Nucleosynthesis
... Double-Shell Burning AGB stars • Helium also gets used up in the core. He continues to fuse into carbon in a shell around a growing, inert carbon core, and H fuses to He in a shell around the helium layer. • The star expands again, ascending the – Asymptotic Giant Branch (AGB stars) – though brief, ...
... Double-Shell Burning AGB stars • Helium also gets used up in the core. He continues to fuse into carbon in a shell around a growing, inert carbon core, and H fuses to He in a shell around the helium layer. • The star expands again, ascending the – Asymptotic Giant Branch (AGB stars) – though brief, ...
File
... Note that there are physical reasons why longlived stars have these properties: They are less luminous because they burn their fuel at a much lower rate than shortlived stars; they burn it at this lower rate because they are less massive (which means less compression and hence a lower fusion rate ...
... Note that there are physical reasons why longlived stars have these properties: They are less luminous because they burn their fuel at a much lower rate than shortlived stars; they burn it at this lower rate because they are less massive (which means less compression and hence a lower fusion rate ...
Stellar evolution
Stellar evolution is the process by which a star changes during its lifetime. Depending on the mass of the star, this lifetime ranges from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. The table shows the lifetimes of stars as a function of their masses. All stars are born from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star.Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase. Stars with at least half the mass of the Sun can also begin to generate energy through the fusion of helium at their core, whereas more-massive stars can fuse heavier elements along a series of concentric shells. Once a star like the Sun has exhausted its nuclear fuel, its core collapses into a dense white dwarf and the outer layers are expelled as a planetary nebula. Stars with around ten or more times the mass of the Sun can explode in a supernova as their inert iron cores collapse into an extremely dense neutron star or black hole. Although the universe is not old enough for any of the smallest red dwarfs to have reached the end of their lives, stellar models suggest they will slowly become brighter and hotter before running out of hydrogen fuel and becoming low-mass white dwarfs.Stellar evolution is not studied by observing the life of a single star, as most stellar changes occur too slowly to be detected, even over many centuries. Instead, astrophysicists come to understand how stars evolve by observing numerous stars at various points in their lifetime, and by simulating stellar structure using computer models.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.