Matariki-Maori New Year
... Looking west this shows the Sun setting - from mid-winter through the equinox to mid-summer (Northern Hemisphere view). What dates are these? ...
... Looking west this shows the Sun setting - from mid-winter through the equinox to mid-summer (Northern Hemisphere view). What dates are these? ...
Star Information ppt.
... Life expectancy of 0.1 MSun star: 0.1 times as much fuel, uses it 0.01 times as fast ...
... Life expectancy of 0.1 MSun star: 0.1 times as much fuel, uses it 0.01 times as fast ...
Surveying the Stars
... • How do we measure the age of a star cluster? • Because all of a cluster’s stars we born at the same time, we can measure a cluster’s age by finding the main sequence turnoff point on an H–R diagram of its stars. The cluster’s age is equal to the hydrogenburning lifetime of the hottest, most lumino ...
... • How do we measure the age of a star cluster? • Because all of a cluster’s stars we born at the same time, we can measure a cluster’s age by finding the main sequence turnoff point on an H–R diagram of its stars. The cluster’s age is equal to the hydrogenburning lifetime of the hottest, most lumino ...
electron degeneracy pressure and white dwarfs
... confined to atomic dimensions (about 10-8 cm); thus neutrons and protons to a space a factor of about 1836 smaller (in round numbers, about 10-11 cm), that number being the ratio of these particles’ masses to that of the electron. Photons -- particles of light -- have rest mass 0. (They also have ...
... confined to atomic dimensions (about 10-8 cm); thus neutrons and protons to a space a factor of about 1836 smaller (in round numbers, about 10-11 cm), that number being the ratio of these particles’ masses to that of the electron. Photons -- particles of light -- have rest mass 0. (They also have ...
Birth - Wayne State University Physics and Astronomy
... Stable (main-sequence) stars maintain equilibrium by producing energy through nuclear fusion in their cores The ability to generate energy by fusion defines a star ...
... Stable (main-sequence) stars maintain equilibrium by producing energy through nuclear fusion in their cores The ability to generate energy by fusion defines a star ...
Document
... What is this nothing which the gas and stars are rapidly orbiting? Only real possibility is a Black Hole! Must have a mass of 2.7£106M¯. Not a black hole from a single stellar collapse, but must be built up over time. We shall meet these again when we come to look at quasars, but we have to ask “Jus ...
... What is this nothing which the gas and stars are rapidly orbiting? Only real possibility is a Black Hole! Must have a mass of 2.7£106M¯. Not a black hole from a single stellar collapse, but must be built up over time. We shall meet these again when we come to look at quasars, but we have to ask “Jus ...
L5 - QUB Astrophysics Research Centre
... introductory articles provided, and supplement this with your own reading. You should attempt to clarify the problem for yourself and understand its importance. In particular you should discuss the following • Why and how have solar neutrinos been observed ? • What is their importance • Define and d ...
... introductory articles provided, and supplement this with your own reading. You should attempt to clarify the problem for yourself and understand its importance. In particular you should discuss the following • Why and how have solar neutrinos been observed ? • What is their importance • Define and d ...
Distance Ladder
... How the technique works: •Figure out how luminous your standard candles are •If you know distance d and brightness B, you can figure this out from: L = 4d2B •To find the distance to another of the same class: •It should have the same luminosity L •Measure its brightness B •Deduce distance from: L = ...
... How the technique works: •Figure out how luminous your standard candles are •If you know distance d and brightness B, you can figure this out from: L = 4d2B •To find the distance to another of the same class: •It should have the same luminosity L •Measure its brightness B •Deduce distance from: L = ...
SSS in young stellar populations: progenitors of the
... So, WD will generally orbit inside Be disk – accretion from Be outflow? • Star forming regions will start producing Be/CO binaries in approx. 5 x 10^7 years ...
... So, WD will generally orbit inside Be disk – accretion from Be outflow? • Star forming regions will start producing Be/CO binaries in approx. 5 x 10^7 years ...
chapter16StarBirth
... • As contraction packs the molecules and dust particles of a cloud fragment closer together, it becomes harder for infrared and radio photons to escape • Thermal energy then begins to build up inside, increasing the internal pressure ...
... • As contraction packs the molecules and dust particles of a cloud fragment closer together, it becomes harder for infrared and radio photons to escape • Thermal energy then begins to build up inside, increasing the internal pressure ...
Star Formation
... • What is a protostar’s source of energy? • How does a protostar’s radius and luminosity change as it contracts? • What is the relation between luminosity, radius, and temperature. • How does a protostar’s mass influence its speed of formation? • What is the Jean’s mass? ...
... • What is a protostar’s source of energy? • How does a protostar’s radius and luminosity change as it contracts? • What is the relation between luminosity, radius, and temperature. • How does a protostar’s mass influence its speed of formation? • What is the Jean’s mass? ...
Teacher`s Show Guide
... Discuss the prospects of interstellar travel given such distances. How long would it take to reach the nearest star system (Alpha Centauri, 4.3 light years distant) in a automobile at 65 miles per hour? In a Apollo spacecraft? On a Voyager spacecraft? Given these distances, discuss prospects of so-c ...
... Discuss the prospects of interstellar travel given such distances. How long would it take to reach the nearest star system (Alpha Centauri, 4.3 light years distant) in a automobile at 65 miles per hour? In a Apollo spacecraft? On a Voyager spacecraft? Given these distances, discuss prospects of so-c ...
PDF - BYU Studies
... Price, including the statement that new stars are created as old ones pass away. Modern astrophysics teaches that stars are formed, enjoy an enormously long “summer” as they fuse hydrogen to helium in their core, then undergo major changes as nuclear fuel runs low, and finally fade away (occasionall ...
... Price, including the statement that new stars are created as old ones pass away. Modern astrophysics teaches that stars are formed, enjoy an enormously long “summer” as they fuse hydrogen to helium in their core, then undergo major changes as nuclear fuel runs low, and finally fade away (occasionall ...
HR4AGN Powerpoint Presentation-a
... the color of an AGN we can get its luminosity – But AGN have no fusion, why would we expect a color-magnitude relation? – The gas that accretes onto the black hole is still hot and so must follow the Blackbody Radiation law. ...
... the color of an AGN we can get its luminosity – But AGN have no fusion, why would we expect a color-magnitude relation? – The gas that accretes onto the black hole is still hot and so must follow the Blackbody Radiation law. ...
PHYS3380_110415_bw - The University of Texas at Dallas
... into its final stages of evolution; at this time the star is AGB star characterized by a carbon-oxygen core, surrounded by a helium burning shell and a hydrogen burning shell. • For stars whose mass is greater than 2.25 M, the electrons in their cores are not degenerate at the time of helium igniti ...
... into its final stages of evolution; at this time the star is AGB star characterized by a carbon-oxygen core, surrounded by a helium burning shell and a hydrogen burning shell. • For stars whose mass is greater than 2.25 M, the electrons in their cores are not degenerate at the time of helium igniti ...
Slide 1
... Turn Off - As the hydrogen fuel in a star's core runs out the core begins to collapse due to gravity and the star moves away from the main sequence. At the turn off nearly all the central fuel is gone. Red Giant Branch - When the central fuel is gone, hydrogen starts to burn in an envelope around a ...
... Turn Off - As the hydrogen fuel in a star's core runs out the core begins to collapse due to gravity and the star moves away from the main sequence. At the turn off nearly all the central fuel is gone. Red Giant Branch - When the central fuel is gone, hydrogen starts to burn in an envelope around a ...
Document
... Type I Supernovae: 1. Binary system: • A sub-Chandrasekhar white dwarf • A less dense companion star 2. Gravity strips material off companion star 3. Dwarf gets more and more massive 4. Mass exceeds Chandrasekhar limit (1.4 Msun) 5. Kablooey 6. Kablooey has a certain absolute magnitude 7. Kablooey ...
... Type I Supernovae: 1. Binary system: • A sub-Chandrasekhar white dwarf • A less dense companion star 2. Gravity strips material off companion star 3. Dwarf gets more and more massive 4. Mass exceeds Chandrasekhar limit (1.4 Msun) 5. Kablooey 6. Kablooey has a certain absolute magnitude 7. Kablooey ...
Nogami, D. - Subaru Telescope
... Spectroscopy of superflare stars with Subaru • Is there really a superflare star which is very similar to the Sun? • We have been currently undergoing a follow-up project of high dispersion spectroscopy of the superflare stars with the Subaru telescope, for checking the rotation velocity, binarity, ...
... Spectroscopy of superflare stars with Subaru • Is there really a superflare star which is very similar to the Sun? • We have been currently undergoing a follow-up project of high dispersion spectroscopy of the superflare stars with the Subaru telescope, for checking the rotation velocity, binarity, ...
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.