Stars with mass less than 0.5 solar masses
... sequence, placed according to their mass. At a certain point in their life the hydrogen in the core finishes. As a conseguence, the nuclear fusion finishes too, and so the star starts to contract under the pressure of its own mass. Then, the destiny of the star depends on its mass: ...
... sequence, placed according to their mass. At a certain point in their life the hydrogen in the core finishes. As a conseguence, the nuclear fusion finishes too, and so the star starts to contract under the pressure of its own mass. Then, the destiny of the star depends on its mass: ...
Chapter20
... which blows the outer layers into space. It is in this wind that dust particles are formed. ...
... which blows the outer layers into space. It is in this wind that dust particles are formed. ...
Stellar Evolution
... • When the hydrogen in the core is almost consumed the balance between gravity pulling in and pressure pushing out is disturbed. • The structure and appearance of the star changes dramatically. • What happens then, depends on the star’s mass. • Two cases: – Low-mass (< 8 x mass of Sun) – High-mass ( ...
... • When the hydrogen in the core is almost consumed the balance between gravity pulling in and pressure pushing out is disturbed. • The structure and appearance of the star changes dramatically. • What happens then, depends on the star’s mass. • Two cases: – Low-mass (< 8 x mass of Sun) – High-mass ( ...
A-105 Homework 1
... 2. (1 pt.) How can the contraction of an inert helium core trigger the ignition of a hydrogen-fusion shell? ...
... 2. (1 pt.) How can the contraction of an inert helium core trigger the ignition of a hydrogen-fusion shell? ...
Document
... • Stars on the main sequence fuse hydrogen in their core to produce thermal pressure. • Longest phase of a star’s life. ...
... • Stars on the main sequence fuse hydrogen in their core to produce thermal pressure. • Longest phase of a star’s life. ...
Supernova worksheet with solutions ()
... Energy Released As: Mostly neutrinos. The explosion also ejects gas (what used to be the star) at very high speeds. Light makes up about 0.01% of the total energy released. ...
... Energy Released As: Mostly neutrinos. The explosion also ejects gas (what used to be the star) at very high speeds. Light makes up about 0.01% of the total energy released. ...
here - University of Toronto Astronomy
... stars- The coolest stars demonstrate spectral lines of molecules and neutral metals while the hottest, bluest stars’ source of spectral lines are ionized helium atoms; the hotter the gas, the faster the molecules or atoms move, the more likely electrons will be disturbed or disrupted; emission and a ...
... stars- The coolest stars demonstrate spectral lines of molecules and neutral metals while the hottest, bluest stars’ source of spectral lines are ionized helium atoms; the hotter the gas, the faster the molecules or atoms move, the more likely electrons will be disturbed or disrupted; emission and a ...
Stellar Evolution
... • When the hydrogen in the core is almost consumed the balance between gravity pulling in and pressure pushing out is disturbed. • The structure and appearance of the star changes dramatically. • What happens then, depends on the star’s mass. • Two cases: – Low-mass (< 8 x mass of Sun) – High-mass ( ...
... • When the hydrogen in the core is almost consumed the balance between gravity pulling in and pressure pushing out is disturbed. • The structure and appearance of the star changes dramatically. • What happens then, depends on the star’s mass. • Two cases: – Low-mass (< 8 x mass of Sun) – High-mass ( ...
Star Life Cycle - GSHS Mrs. Francomb
... Pumbaa: Oh. Gee. I always thought that they were balls of gas burning billions of miles away. Timon: Pumbaa, wit' you, everything's gas. ...
... Pumbaa: Oh. Gee. I always thought that they were balls of gas burning billions of miles away. Timon: Pumbaa, wit' you, everything's gas. ...
iClicker Questions
... The shockwave from a nearby supernova b) The shockwave from a newly formed high-mass star that is nearby c) The shockwave experienced by the cloud as it passes through a spiral arm d) All of the above ...
... The shockwave from a nearby supernova b) The shockwave from a newly formed high-mass star that is nearby c) The shockwave experienced by the cloud as it passes through a spiral arm d) All of the above ...
Slide 1
... The Evolution of a Star: Hertzsprung-Russell Diagram (1910): A plot of Luminosity vs Surface Temperature, T (see overlay). A one solar mass star like the sun goes through the stages of: protostar, main sequence, ...
... The Evolution of a Star: Hertzsprung-Russell Diagram (1910): A plot of Luminosity vs Surface Temperature, T (see overlay). A one solar mass star like the sun goes through the stages of: protostar, main sequence, ...
Chapter 29 Stellar Evolution
... photo at left compare? • What are some ways the stars in the photo could be grouped or classified? ...
... photo at left compare? • What are some ways the stars in the photo could be grouped or classified? ...
Stellar evolution
... In stars like the Sun or less massive, H -> He most efficient through proton-proton chain. In higher mass stars, "CNO cycle" more ...
... In stars like the Sun or less massive, H -> He most efficient through proton-proton chain. In higher mass stars, "CNO cycle" more ...
Ch. 27 Stars & Galaxies
... • Scientists have developed theories about the evolution of stars by studying stars in different stages of development. ...
... • Scientists have developed theories about the evolution of stars by studying stars in different stages of development. ...
AST301.Ch21.StellarExpl - University of Texas Astronomy
... have huge energies and photodisintegrate the iron into protons and neutrons. This absorbs even more thermal (heat) energy, so the core collapses even faster! Gravity is having its way… The protons combine with electrons to give neutrons and neutrinos (which escape immediately—later we’ll see that th ...
... have huge energies and photodisintegrate the iron into protons and neutrons. This absorbs even more thermal (heat) energy, so the core collapses even faster! Gravity is having its way… The protons combine with electrons to give neutrons and neutrinos (which escape immediately—later we’ll see that th ...
astronomy 2 review sheet - Hicksville Public Schools
... 18. Describe a meteor, meteoroid and a meteorite. METEOR- STREAK OF LIGHT AS A METE0ROID BURNS UP IN THE EARTH’S ATMOSPHERE. METEOROID- A CHUNK OF ROCK OR DUST IN SPACE. METEORITE- A METEOROID THAT HITS THE EARTH’S SURFACE. 19. What force pulls together matter in stars? GRAVITY 20. If you look at an ...
... 18. Describe a meteor, meteoroid and a meteorite. METEOR- STREAK OF LIGHT AS A METE0ROID BURNS UP IN THE EARTH’S ATMOSPHERE. METEOROID- A CHUNK OF ROCK OR DUST IN SPACE. METEORITE- A METEOROID THAT HITS THE EARTH’S SURFACE. 19. What force pulls together matter in stars? GRAVITY 20. If you look at an ...
Stellar Deaths - Mid
... 1) formed at about same time 2) are at about the same distance 3) have same chemical composition The ONLY variable property among stars in a cluster is mass! ...
... 1) formed at about same time 2) are at about the same distance 3) have same chemical composition The ONLY variable property among stars in a cluster is mass! ...
Chapter 16
... Fusion of Iron (Fe). Iron takes more energy to fuse than can be obtained from it, and is an example of an endothermic process, which does not occur in stars. As stars produce nuclei with masses progressively nearer the iron peak of the binding energy curve, less and less energy is produced per kg of ...
... Fusion of Iron (Fe). Iron takes more energy to fuse than can be obtained from it, and is an example of an endothermic process, which does not occur in stars. As stars produce nuclei with masses progressively nearer the iron peak of the binding energy curve, less and less energy is produced per kg of ...
Lecture 19 Review
... to make a heavier element. At this point gravitational collapse occurs followed by a catastrophic rebound. A fast neutron process produces heavy elements all the way up to Plutonium. There is a strong neutron burst and a supernova explosion. For a few days the supernova has a luminosity L = 10 billi ...
... to make a heavier element. At this point gravitational collapse occurs followed by a catastrophic rebound. A fast neutron process produces heavy elements all the way up to Plutonium. There is a strong neutron burst and a supernova explosion. For a few days the supernova has a luminosity L = 10 billi ...
Star Jeopardy Review #2
... Star formation may be triggered by __________ which help gravity through compression of interstellar clouds to greater densities. ...
... Star formation may be triggered by __________ which help gravity through compression of interstellar clouds to greater densities. ...
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.