Type 1a Supernovae - RanelaghALevelPhysics
... Type 1a Supernova The white dwarf reaches a larger mass, approaching the Chandrasekhar limit But just before it would collapse into a neutron star (within 1% of the limit), the temperature and density inside the core increase enough to allow the fusion of carbon to take place. ...
... Type 1a Supernova The white dwarf reaches a larger mass, approaching the Chandrasekhar limit But just before it would collapse into a neutron star (within 1% of the limit), the temperature and density inside the core increase enough to allow the fusion of carbon to take place. ...
Overview IR Astronomy Explore hidden universe , Cosmic dust, Cool
... Cygnus region Red : seeing the light from billions of stars, particularly the largest, brightest ones. The dark bands where vast clouds of dust block our view NIR : stars, but now it better traces the smaller, cooler ones. the lanes of dust have become ...
... Cygnus region Red : seeing the light from billions of stars, particularly the largest, brightest ones. The dark bands where vast clouds of dust block our view NIR : stars, but now it better traces the smaller, cooler ones. the lanes of dust have become ...
stellar evolution the flowchart of start
... 2. Where on the HR diagram is it? What is its energy source? ...
... 2. Where on the HR diagram is it? What is its energy source? ...
How and when did the universe begin
... matter continually comes to life in the spaces between the receding galaxies. Naturally, continuous creation of matter from empty space has met with criticism. Astronomers can figure out how old a galaxy or star is by measuring its distance from Earth. Since astronomers haven't found quasars that f ...
... matter continually comes to life in the spaces between the receding galaxies. Naturally, continuous creation of matter from empty space has met with criticism. Astronomers can figure out how old a galaxy or star is by measuring its distance from Earth. Since astronomers haven't found quasars that f ...
The correct answers are written in bold, italic and underlined. The
... white dwarf, bringing the white dwarf up to the Chandrasekhar mass limit. • The core of a massive star is gradually transformed into iron by thermonuclear fusion reactions until it collapses, causing the outer layers to explode off the star. • Helium shell flashes push the outer layers of an asympto ...
... white dwarf, bringing the white dwarf up to the Chandrasekhar mass limit. • The core of a massive star is gradually transformed into iron by thermonuclear fusion reactions until it collapses, causing the outer layers to explode off the star. • Helium shell flashes push the outer layers of an asympto ...
Cosmology - RHIG - Wayne State University
... Masses of galaxies are found from the orbital motion of their stars. Stars in a more massive galaxy orbit faster than those in a lower mass galaxy because the greater gravity force of the massive galaxy causes larger accelerations of its stars. By measuring the star speeds, one finds out how much gr ...
... Masses of galaxies are found from the orbital motion of their stars. Stars in a more massive galaxy orbit faster than those in a lower mass galaxy because the greater gravity force of the massive galaxy causes larger accelerations of its stars. By measuring the star speeds, one finds out how much gr ...
Astronomy 82 - Problem Set #1
... supernova had been expanding for about 900 years in 1983 – therefore the supernova must have been seen to explode around the year (1983 – 900) =1083 ~ 1100 AD. Again, this number is no secret – the Crab Nebula was observed by astronomers in several countries when its light reached earth in 1054 AD. ...
... supernova had been expanding for about 900 years in 1983 – therefore the supernova must have been seen to explode around the year (1983 – 900) =1083 ~ 1100 AD. Again, this number is no secret – the Crab Nebula was observed by astronomers in several countries when its light reached earth in 1054 AD. ...
nuclear decays, radioactivity, and reactions
... the earth is about 4.5 109 years old, it is believed to have formed as a cold aggregate of smaller bodies, containing a lot of Fe, Ni, and silicates, then the whole thing melted due to the energy released by radioactive processes!!! the metals went down (as they are heavier) and make up the core, th ...
... the earth is about 4.5 109 years old, it is believed to have formed as a cold aggregate of smaller bodies, containing a lot of Fe, Ni, and silicates, then the whole thing melted due to the energy released by radioactive processes!!! the metals went down (as they are heavier) and make up the core, th ...
Chapter 17 Star Stuff Agenda How does a star`s mass affect nuclear
... Life Track after Main Sequence • Observations of star clusters show that a star becomes larger, ...
... Life Track after Main Sequence • Observations of star clusters show that a star becomes larger, ...
ppt
... This means that in a planeparallel atmosphere, the radiative flux must have the same value at every level in the atmosphere, including its surface…. ...
... This means that in a planeparallel atmosphere, the radiative flux must have the same value at every level in the atmosphere, including its surface…. ...
Narrated by Whoopi Goldberg - American Museum of Natural History
... space along with its planetary system until finally, four and a half billion years later, it settles into our familiar galactic neighborhood. ...
... space along with its planetary system until finally, four and a half billion years later, it settles into our familiar galactic neighborhood. ...
PART 3 Galaxies
... The primary reason that massive O-type stars are not found in the galactic halo is because they are a) too massive to be kicked into the halo from the disk. b) so massive that they settle into the thinner disk. c) too short-lived to have persisted from halo formation until today. d) closer to us in ...
... The primary reason that massive O-type stars are not found in the galactic halo is because they are a) too massive to be kicked into the halo from the disk. b) so massive that they settle into the thinner disk. c) too short-lived to have persisted from halo formation until today. d) closer to us in ...
Hydrostatic Equilibrium of Hypothetical Quark Stars
... either by adding newly discovered elementary particles or by assuming some interactions between these elementary particles. A primitive and straightforward question then arises: What state occurs at the density higher than hyperon stars? No one can answer this question now, as our knowledge of stron ...
... either by adding newly discovered elementary particles or by assuming some interactions between these elementary particles. A primitive and straightforward question then arises: What state occurs at the density higher than hyperon stars? No one can answer this question now, as our knowledge of stron ...
16.1 A Little History
... in order of increasing mass. The solid curve is a Salpeter Initial Mass Function with slope α =252.35 (Lecture 11.9) between Mmin = 8.5M and Mmax = 16.5M , which gives the ...
... in order of increasing mass. The solid curve is a Salpeter Initial Mass Function with slope α =252.35 (Lecture 11.9) between Mmin = 8.5M and Mmax = 16.5M , which gives the ...
Xtra_credit_MC_chapt_10−12_2014.txt Xtra_credit_MC_chapt_10
... in the video is: a) just to the left of your viewing direction b) in your viewing direction c) just to the right of your viewing direction d) a) or c) depending on the time of year e) none of the above 3) Then 6 months later (in the video) at the instant of the last vestige of the Sun on the western ...
... in the video is: a) just to the left of your viewing direction b) in your viewing direction c) just to the right of your viewing direction d) a) or c) depending on the time of year e) none of the above 3) Then 6 months later (in the video) at the instant of the last vestige of the Sun on the western ...
... This is because of the many uncertainties in the analysis. The measurements of the spectra are probably the least uncertain. The optical spectra usually only refers to a small region in the nebula, as well as a limited spectral region. To get a more complete picture they should be combined with ultr ...
Astrophysics Pristine CNO abundances from Magellanic Cloud B stars
... from LMC H ii regions as carried out/compiled by Garnett (1999). Finally, we also include the Solar System composition (Grevesse & Sauval 1998) as a reference. Note that a recent redetermination of the solar oxygen abundance from [O i] 6300 based on 3D hydrodynamical computations (Allende Prieto et ...
... from LMC H ii regions as carried out/compiled by Garnett (1999). Finally, we also include the Solar System composition (Grevesse & Sauval 1998) as a reference. Note that a recent redetermination of the solar oxygen abundance from [O i] 6300 based on 3D hydrodynamical computations (Allende Prieto et ...
The Galactic Halo
... elements (including the lowest [Fe/H] star yet discovered), and lack of over-abundances of neutron-capture elements (CEMP-no stars) Associated with production by “faint SNe” – progenitors with mass on the order of 10-100 Mo undergoing mixing and fallback, or rapidly rotating mega metal-poor (MMP; [F ...
... elements (including the lowest [Fe/H] star yet discovered), and lack of over-abundances of neutron-capture elements (CEMP-no stars) Associated with production by “faint SNe” – progenitors with mass on the order of 10-100 Mo undergoing mixing and fallback, or rapidly rotating mega metal-poor (MMP; [F ...
Fe I/Fe II ionization equilibrium in cool stars: NLTE versus LTE
... 965 energy levels for Fe I. A comparison with the calculated Fe I atomic structure (Kurucz (2007)) reveals that the system of measured levels is nearly complete below excitation energy, Eexc , 5.6 eV, however, laboratory experiments do not see most of the highexcitation levels with Eexc > 7.1 eV. As ...
... 965 energy levels for Fe I. A comparison with the calculated Fe I atomic structure (Kurucz (2007)) reveals that the system of measured levels is nearly complete below excitation energy, Eexc , 5.6 eV, however, laboratory experiments do not see most of the highexcitation levels with Eexc > 7.1 eV. As ...
Powerpoint
... C. Inflationary Theory - predicts that there was a sudden expansion when the universe was very young, more extreme than predicted by the big bang theory! • Considered to be a “revised” Big Bang theory • The universe expanded and cooled until about 10-35 second after the big bang when it became so ...
... C. Inflationary Theory - predicts that there was a sudden expansion when the universe was very young, more extreme than predicted by the big bang theory! • Considered to be a “revised” Big Bang theory • The universe expanded and cooled until about 10-35 second after the big bang when it became so ...
A noble record
... ing the very early stages of the formation of the solar system. An important factor is the abundance of the parent isotope in meteorites, which in turn determines how widespread is the corresponding radiogenic product. The radioactive isotope of potassium (40K) is by far the most abundant parent iso ...
... ing the very early stages of the formation of the solar system. An important factor is the abundance of the parent isotope in meteorites, which in turn determines how widespread is the corresponding radiogenic product. The radioactive isotope of potassium (40K) is by far the most abundant parent iso ...
binary stars
... • If the Sun had more mass, it would have more gravity, and its center would be under greater pressure. The greater the pressure, the greater the temperature, and the more violent the nuclear collisions. More fusion would occur, and more energy would be produced. This explains the main sequence! • ...
... • If the Sun had more mass, it would have more gravity, and its center would be under greater pressure. The greater the pressure, the greater the temperature, and the more violent the nuclear collisions. More fusion would occur, and more energy would be produced. This explains the main sequence! • ...
cosmic ray transport and production in the galaxy: a
... size of the time step and the number of trajectories play a major role in describing the contribution of possible sources in the Galaxy. In order to have satisfactory statistics, the size of the time step must be small and the process is averaged over a few thousand trajectories. In order to describ ...
... size of the time step and the number of trajectories play a major role in describing the contribution of possible sources in the Galaxy. In order to have satisfactory statistics, the size of the time step must be small and the process is averaged over a few thousand trajectories. In order to describ ...
Earth and Beyond - Swinton Community School
... If the Sun, they thought, was powered by chemical reactions how has it managed to stay ‘burning’ for millions of years? There must have been another process producing the energy from the Sun…………. Nuclear Fusion. What two elements constitute most of the Sun? Hydrogen and helium How old is the Sun? Fo ...
... If the Sun, they thought, was powered by chemical reactions how has it managed to stay ‘burning’ for millions of years? There must have been another process producing the energy from the Sun…………. Nuclear Fusion. What two elements constitute most of the Sun? Hydrogen and helium How old is the Sun? Fo ...
NGC 3370 Spiral Galaxy - University of Kentucky
... NGC 4526, distance ~ 200 million light years. ...
... NGC 4526, distance ~ 200 million light years. ...
Nucleosynthesis
Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and neutrons. The first nuclei were formed about three minutes after the Big Bang, through the process called Big Bang nucleosynthesis. It was then that hydrogen and helium formed to become the content of the first stars, and this primeval process is responsible for the present hydrogen/helium ratio of the cosmos.With the formation of stars, heavier nuclei were created from hydrogen and helium by stellar nucleosynthesis, a process that continues today. Some of these elements, particularly those lighter than iron, continue to be delivered to the interstellar medium when low mass stars eject their outer envelope before they collapse to form white dwarfs. The remains of their ejected mass form the planetary nebulae observable throughout our galaxy.Supernova nucleosynthesis within exploding stars by fusing carbon and oxygen is responsible for the abundances of elements between magnesium (atomic number 12) and nickel (atomic number 28). Supernova nucleosynthesis is also thought to be responsible for the creation of rarer elements heavier than iron and nickel, in the last few seconds of a type II supernova event. The synthesis of these heavier elements absorbs energy (endothermic) as they are created, from the energy produced during the supernova explosion. Some of those elements are created from the absorption of multiple neutrons (the R process) in the period of a few seconds during the explosion. The elements formed in supernovas include the heaviest elements known, such as the long-lived elements uranium and thorium.Cosmic ray spallation, caused when cosmic rays impact the interstellar medium and fragment larger atomic species, is a significant source of the lighter nuclei, particularly 3He, 9Be and 10,11B, that are not created by stellar nucleosynthesis.In addition to the fusion processes responsible for the growing abundances of elements in the universe, a few minor natural processes continue to produce very small numbers of new nuclides on Earth. These nuclides contribute little to their abundances, but may account for the presence of specific new nuclei. These nuclides are produced via radiogenesis (decay) of long-lived, heavy, primordial radionuclides such as uranium and thorium. Cosmic ray bombardment of elements on Earth also contribute to the presence of rare, short-lived atomic species called cosmogenic nuclides.