Explosion and remnants of massive stars
... Type Ia supernovae are fundamentally different from other SN types, because they are not associated with the core collapse of massive stars. Instead they are caused by the thermonuclear explosion of a CO white dwarf that reaches a critical mass for carbon ignition. Carbon-burning reactions can occur ...
... Type Ia supernovae are fundamentally different from other SN types, because they are not associated with the core collapse of massive stars. Instead they are caused by the thermonuclear explosion of a CO white dwarf that reaches a critical mass for carbon ignition. Carbon-burning reactions can occur ...
lecture19 - Stony Brook University
... it remains as a Neutron star. Recall that the neutron core formed just before the supernova erupted had very high density. The neutrons are as close as quantum mechanics will allow them (degenerate). The density of the neutron star is about the same as inside an nucleus of the atom – but for the neu ...
... it remains as a Neutron star. Recall that the neutron core formed just before the supernova erupted had very high density. The neutrons are as close as quantum mechanics will allow them (degenerate). The density of the neutron star is about the same as inside an nucleus of the atom – but for the neu ...
Grade 9 Science EXAM REVIEW – ASTRONOMY
... Therefore Neptune is 30.02 AU from the Sun. 11. Define each of the following terms: asteroid = a rocky object smaller than a planet that orbits a star comet = small, irregularly shaped bodies that are made primarily of gas and ice meteor = a small body of matter from outer space that comes into the ...
... Therefore Neptune is 30.02 AU from the Sun. 11. Define each of the following terms: asteroid = a rocky object smaller than a planet that orbits a star comet = small, irregularly shaped bodies that are made primarily of gas and ice meteor = a small body of matter from outer space that comes into the ...
The Swansong of Stars Orbiting Massive Black Holes
... LISA will be able to detect compact objects that spiral into a MBH by GW emission from up to a distance of a Gpc. The signal is expected to be weak. To detect it, it is necessary to know in advance the shape of the wave trains, and to do that, it is necessary to know the eccentricity of the inspiral ...
... LISA will be able to detect compact objects that spiral into a MBH by GW emission from up to a distance of a Gpc. The signal is expected to be weak. To detect it, it is necessary to know in advance the shape of the wave trains, and to do that, it is necessary to know the eccentricity of the inspiral ...
Part 1- The Basics
... temperature) to bottom-right (low luminosity and low surface temperature) – 90% stars in this band – The Sun is one of main sequence stars – Hydrogen burning as energy source ...
... temperature) to bottom-right (low luminosity and low surface temperature) – 90% stars in this band – The Sun is one of main sequence stars – Hydrogen burning as energy source ...
Black Holes - University of Surrey
... Black holes may form during the course of stellar evolution. As nuclear fuels are exhausted in the core of a star, the pressure associated with their heat is no longer available to resist contraction of the core to ever higher densities. Two new types of pressure arise at densities a million and a m ...
... Black holes may form during the course of stellar evolution. As nuclear fuels are exhausted in the core of a star, the pressure associated with their heat is no longer available to resist contraction of the core to ever higher densities. Two new types of pressure arise at densities a million and a m ...
Presentation - University of Idaho
... Luminosity = Total power emitted by star in the form of light. ...
... Luminosity = Total power emitted by star in the form of light. ...
B/W
... Sun and interstellar medium Typically: Hydrogen 90% by number; Helium 10%; other elements (metals) ¿ 1 % (by mass: X ' 0.70, Y ' 0.28, Z ' 0.02) • Globular cluster stars: Metal deficient compared to Sun by factors of 10 – 1000, Hydrogen and helium normal Assuming uniform initial composition for the ...
... Sun and interstellar medium Typically: Hydrogen 90% by number; Helium 10%; other elements (metals) ¿ 1 % (by mass: X ' 0.70, Y ' 0.28, Z ' 0.02) • Globular cluster stars: Metal deficient compared to Sun by factors of 10 – 1000, Hydrogen and helium normal Assuming uniform initial composition for the ...
ISP 205: Visions of the Universe Fall 2001 Professor: ER Capriotti
... C. a large city, metallic D. the Earth's orbit, gaseous E. the Earth, metallic 75. The Chandrasekhar limit implies that stars ending up more massive than 1.4 solar masses cannot become A. giant stars B. supernovae C. neutron stars D. black holes E. white dwarfs 76. Black holes are A. places where no ...
... C. a large city, metallic D. the Earth's orbit, gaseous E. the Earth, metallic 75. The Chandrasekhar limit implies that stars ending up more massive than 1.4 solar masses cannot become A. giant stars B. supernovae C. neutron stars D. black holes E. white dwarfs 76. Black holes are A. places where no ...
- Lorentz Center
... • Just as in AGB stars, the accretion of helium leads to thermally unstable flashes • These are mass and accretion rate dependent • Squares (triangles) are for 0.6 (0.8) M WDs, triangles for >1.0 M ...
... • Just as in AGB stars, the accretion of helium leads to thermally unstable flashes • These are mass and accretion rate dependent • Squares (triangles) are for 0.6 (0.8) M WDs, triangles for >1.0 M ...
How long would the Sun shine? Fuel = Gravitational Energy? Fuel
... – The core keeps shrinking… Gravitational force is not balanced by thermal pressure… Where would the gravitational energy go… – Type II Supernova!! (Hydrogen lines should be seen.) ...
... – The core keeps shrinking… Gravitational force is not balanced by thermal pressure… Where would the gravitational energy go… – Type II Supernova!! (Hydrogen lines should be seen.) ...
Equations of Stellar Structure Stellar structure and evolution can be
... the radial coordinate of the star the stellar mass contained within radius, r the luminosity generated within radius r the gas + radiation pressure at r the density at r the mass fraction of the star that is hydrogen the mass fraction of the star that is helium the mass fraction of the star that is ...
... the radial coordinate of the star the stellar mass contained within radius, r the luminosity generated within radius r the gas + radiation pressure at r the density at r the mass fraction of the star that is hydrogen the mass fraction of the star that is helium the mass fraction of the star that is ...
red giant - Teacher Pages
... Stars, cont. e. Held together by gravitational forces f. Hydrogen combines to form helium on stars. This is called a fusion reaction and produces energy g. Our sun is a typical star ...
... Stars, cont. e. Held together by gravitational forces f. Hydrogen combines to form helium on stars. This is called a fusion reaction and produces energy g. Our sun is a typical star ...
The Family of Stars
... but Sirius B is a white dwarf star, with a radius ~ 560 times smaller than Spica B. ...
... but Sirius B is a white dwarf star, with a radius ~ 560 times smaller than Spica B. ...
printer-friendly version of benchmark
... 3. Students incorrectly think that our Sun will end as a supernova explosion. All stars that are about 8 MSun or greater will end as a supernova, leaving some kind of stellar remnant (e.g., a neutron star or black hole). Specifically, these massive stars will end as a Type II supernova. In massive ...
... 3. Students incorrectly think that our Sun will end as a supernova explosion. All stars that are about 8 MSun or greater will end as a supernova, leaving some kind of stellar remnant (e.g., a neutron star or black hole). Specifically, these massive stars will end as a Type II supernova. In massive ...
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.