Section 25.2 Stellar Evolution
... Match each death description with its star. Death Description 7. forms a red giant, which then collapses into a red dwarf and forms a planetary nebula 8. blows up in a supernova explosion 9. does not form a red giant; collapses directly into a white dwarf ...
... Match each death description with its star. Death Description 7. forms a red giant, which then collapses into a red dwarf and forms a planetary nebula 8. blows up in a supernova explosion 9. does not form a red giant; collapses directly into a white dwarf ...
Life and Death of a Star The Universe Season 1 Episode 10
... Neutron Stars: After a type 2 supernova, the core is compressed to something about 10 miles wide. The electrons combine with protons to make neutrons. The core can now be compressed to a certain point, smaller than a white dwarf. Neutron stars spin. They have a strong magnetic field. Electrons move ...
... Neutron Stars: After a type 2 supernova, the core is compressed to something about 10 miles wide. The electrons combine with protons to make neutrons. The core can now be compressed to a certain point, smaller than a white dwarf. Neutron stars spin. They have a strong magnetic field. Electrons move ...
MSci Astrophysics 210PHY412 - Queen's University Belfast
... The evolution of massive stars have the following general characteristics and differences to lower mass evolution 1. The electrons in their cores do not become degenerate until the final burning stages, when iron core is reached 2. Mass-loss plays an important role in the entire evolution (we will c ...
... The evolution of massive stars have the following general characteristics and differences to lower mass evolution 1. The electrons in their cores do not become degenerate until the final burning stages, when iron core is reached 2. Mass-loss plays an important role in the entire evolution (we will c ...
Week 5 - OSU Astronomy
... • Nuclear reactions are very sensitive to temperature – small increase in temperature produces large increase in reaction rates and energy production – this is good! It provides stability to the star – If core temperature too low, gravity forces it to contract, temperature goes up, more energy produ ...
... • Nuclear reactions are very sensitive to temperature – small increase in temperature produces large increase in reaction rates and energy production – this is good! It provides stability to the star – If core temperature too low, gravity forces it to contract, temperature goes up, more energy produ ...
CoRoT: a space project to listen to the songs of the stars
... be launched on December 27, 2006. Its main purpose is to study the interiors of the stars and to detect planets orbiting around the Sun-like stars (the acronym CoRoT stands for Convection and Rotation of stars and planetary Transits. CoRoT is a mission of the French CNES space agency in partnership ...
... be launched on December 27, 2006. Its main purpose is to study the interiors of the stars and to detect planets orbiting around the Sun-like stars (the acronym CoRoT stands for Convection and Rotation of stars and planetary Transits. CoRoT is a mission of the French CNES space agency in partnership ...
Classes 12 to 13 - physics.udel.edu
... White dwarf cooling – Mestel theory A white dwarf has an electron degenerate core with a thin non-degenerate envelope (m ≈ 10-4 M☉). In the core the electrons have a large mean free path because almost all available energy levels in the Fermi ‘sea’ are filled. This results in a high thermal conducti ...
... White dwarf cooling – Mestel theory A white dwarf has an electron degenerate core with a thin non-degenerate envelope (m ≈ 10-4 M☉). In the core the electrons have a large mean free path because almost all available energy levels in the Fermi ‘sea’ are filled. This results in a high thermal conducti ...
Lec10_2D
... stellar remnant. In the remnant, the electrons of atoms are crushed into their nucleus. The star becomes one gigantic atomic nucleus made up only of neutrons – a neutron star. ...
... stellar remnant. In the remnant, the electrons of atoms are crushed into their nucleus. The star becomes one gigantic atomic nucleus made up only of neutrons – a neutron star. ...
Stellar Evolution after the Main Sequence
... The Earth will vaporize. The Earth will melt into a cinder, but remain ...
... The Earth will vaporize. The Earth will melt into a cinder, but remain ...
Components of the Milky Way
... is ~ GM2 / R. Energy is liberated as protostars (and brown dwarfs and giant planets) contract. Eventually, central temperature becomes high enough for fusion of H -> He. Contraction ceases - main sequence phase. Estimate the main-sequence lifetime: • Fusion of H to He yields e = 6 x 1018 erg / g • S ...
... is ~ GM2 / R. Energy is liberated as protostars (and brown dwarfs and giant planets) contract. Eventually, central temperature becomes high enough for fusion of H -> He. Contraction ceases - main sequence phase. Estimate the main-sequence lifetime: • Fusion of H to He yields e = 6 x 1018 erg / g • S ...
Friday, February 12, 2016 Astronomy in the news?
... To understand the roles of thermal pressure, charge repulsion, and the strong nuclear force in controlling the way massive stars evolve. ...
... To understand the roles of thermal pressure, charge repulsion, and the strong nuclear force in controlling the way massive stars evolve. ...
PhD Qualifying Exam (2010) --
... the Jeans mass. For a cloud of uniform temperature T, and average density ρ, find its Jeans mass. (5 points) (b) As a cloud collapses often it fragments, until a lower mass limit of fragments is reached. Find this minimum mass. (5 points) (c) Assuming that a star of mass M has no nuclear energy sour ...
... the Jeans mass. For a cloud of uniform temperature T, and average density ρ, find its Jeans mass. (5 points) (b) As a cloud collapses often it fragments, until a lower mass limit of fragments is reached. Find this minimum mass. (5 points) (c) Assuming that a star of mass M has no nuclear energy sour ...
Life Cycle of a Star - Intervention Worksheet
... become later in its life; typically have the same ...
... become later in its life; typically have the same ...
5Stars_Part_Two
... 3. Its location was fixed with respect to the stars. From Jay Pasachoff’s “Contemporary Astronomy” ...
... 3. Its location was fixed with respect to the stars. From Jay Pasachoff’s “Contemporary Astronomy” ...
Milky Way Galaxy
... A star is a big ball of gas which gives off both heat and light. So where do stars come from? What happens to them as they grow older? A galaxy contains clouds of dust and gas, as well as stars. It is in the clouds of dust and gas that stars are born. As more and more of the gas (which is mostly hyd ...
... A star is a big ball of gas which gives off both heat and light. So where do stars come from? What happens to them as they grow older? A galaxy contains clouds of dust and gas, as well as stars. It is in the clouds of dust and gas that stars are born. As more and more of the gas (which is mostly hyd ...
Chapter 8 Lesson 4 Stars and Constellations
... long as it is daylight, our part of Earth is facing the Sun, and the Sun is giving off light energy as ...
... long as it is daylight, our part of Earth is facing the Sun, and the Sun is giving off light energy as ...
Astronomy 115 Homework Set #1 – Due: Thursday, Feb
... In what ways did supernova 1987A confirm our models of supernova explosions? In what ways did it challenge it? ...
... In what ways did supernova 1987A confirm our models of supernova explosions? In what ways did it challenge it? ...
The Sizes of Stars
... the nuclear collisions. More fusion would occur, and more energy would be produced. This explains the main sequence! ...
... the nuclear collisions. More fusion would occur, and more energy would be produced. This explains the main sequence! ...
Star formation and Evolution
... hydrogen into helium. Because stars shine by those nuclear reactions, they have a finite life span. The theory of stellar evolution describes how stars form and change during that life span. Stars are formed when part of a interstellar gas cloud contracts under its own gravitational force; as it col ...
... hydrogen into helium. Because stars shine by those nuclear reactions, they have a finite life span. The theory of stellar evolution describes how stars form and change during that life span. Stars are formed when part of a interstellar gas cloud contracts under its own gravitational force; as it col ...
Main-sequence stage Stellar lifetimes
... sources of H and He fusion. – Star returns to red as an asymptotic giant-branch (AGB) star. – Core cannot become hot enough for further fusion. – Within 104 to 105 years, star moves through the envelope ejection phase -the planetary nebula stage. – Leaves the remnant core: a hot white dwarf object w ...
... sources of H and He fusion. – Star returns to red as an asymptotic giant-branch (AGB) star. – Core cannot become hot enough for further fusion. – Within 104 to 105 years, star moves through the envelope ejection phase -the planetary nebula stage. – Leaves the remnant core: a hot white dwarf object w ...
How stars form slide show File
... •Massive protostars evolve to be normal (main sequence) stars very quickly (10,000 years); less massive stars evolve more slowly, up to 10 million years. •Eventually the core of the protostar becomes hot enough for nuclear fusion to take place, this needs a temperature of at least 15 million Kelvin ...
... •Massive protostars evolve to be normal (main sequence) stars very quickly (10,000 years); less massive stars evolve more slowly, up to 10 million years. •Eventually the core of the protostar becomes hot enough for nuclear fusion to take place, this needs a temperature of at least 15 million Kelvin ...
powerpoint
... NEBULA (cloud of gas and dust)… aka the STELLAR NURSERY • The nebula begins to contract due to gravity in response to some interstellar disturbance • One or more PROTOSTARS are formed ...
... NEBULA (cloud of gas and dust)… aka the STELLAR NURSERY • The nebula begins to contract due to gravity in response to some interstellar disturbance • One or more PROTOSTARS are formed ...
Introduction to pulsars - Pulsar Search Collaboratory
... Final fate of a star depends on how big the star was to start with. ...
... Final fate of a star depends on how big the star was to start with. ...
Stars and The Universe
... The core becomes so compressed that protons (+) and electrons (-) fuse to create neutrons… ...
... The core becomes so compressed that protons (+) and electrons (-) fuse to create neutrons… ...
Main sequence
In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell. Stars on this band are known as main-sequence stars or ""dwarf"" stars.After a star has formed, it generates thermal energy in the dense core region through the nuclear fusion of hydrogen atoms into helium. During this stage of the star's lifetime, it is located along the main sequence at a position determined primarily by its mass, but also based upon its chemical composition and other factors. All main-sequence stars are in hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of gravitational collapse from the overlying layers. The strong dependence of the rate of energy generation in the core on the temperature and pressure helps to sustain this balance. Energy generated at the core makes its way to the surface and is radiated away at the photosphere. The energy is carried by either radiation or convection, with the latter occurring in regions with steeper temperature gradients, higher opacity or both.The main sequence is sometimes divided into upper and lower parts, based on the dominant process that a star uses to generate energy. Stars below about 1.5 times the mass of the Sun (or 1.5 solar masses (M☉)) primarily fuse hydrogen atoms together in a series of stages to form helium, a sequence called the proton–proton chain. Above this mass, in the upper main sequence, the nuclear fusion process mainly uses atoms of carbon, nitrogen and oxygen as intermediaries in the CNO cycle that produces helium from hydrogen atoms. Main-sequence stars with more than two solar masses undergo convection in their core regions, which acts to stir up the newly created helium and maintain the proportion of fuel needed for fusion to occur. Below this mass, stars have cores that are entirely radiative with convective zones near the surface. With decreasing stellar mass, the proportion of the star forming a convective envelope steadily increases, whereas main-sequence stars below 0.4 M☉ undergo convection throughout their mass. When core convection does not occur, a helium-rich core develops surrounded by an outer layer of hydrogen.In general, the more massive a star is, the shorter its lifespan on the main sequence. After the hydrogen fuel at the core has been consumed, the star evolves away from the main sequence on the HR diagram. The behavior of a star now depends on its mass, with stars below 0.23 M☉ becoming white dwarfs directly, whereas stars with up to ten solar masses pass through a red giant stage. More massive stars can explode as a supernova, or collapse directly into a black hole.