Some formulas for astronomy ASTR 122 Fall Quarter 2007 D. E.
... while for photon absorption by an atom after before + hν = Eatom Eatom ...
... while for photon absorption by an atom after before + hν = Eatom Eatom ...
![Lectures 10 & 11 powerpoint (stellar formation) [movie below]](http://s1.studyres.com/store/data/008083226_1-fec717da713794a7feea61d4eec0ceb1-300x300.png)
Lectures 10 & 11 powerpoint (stellar formation) [movie below]
... The Source of Stellar Energy Stars produce energy by nuclear fusion of hydrogen into helium. Q: How does the sun fuse H to He? ...
... The Source of Stellar Energy Stars produce energy by nuclear fusion of hydrogen into helium. Q: How does the sun fuse H to He? ...
Astronomy
... What type of star is Rigel? – A supergiant Which is bigger, Alpha Centauri or the Sun? – Alpha Centauri ...
... What type of star is Rigel? – A supergiant Which is bigger, Alpha Centauri or the Sun? – Alpha Centauri ...
The human race has made great strides in the last few centuries
... By the time that a microsecond has passed after the Big Bang, our physics is in better shape and our models have made remarkable and verifiable predications. We view the Universe as an expanding ball of hot plasma in thermal equilibrium with small density variations imprinted from quantum phenomena ...
... By the time that a microsecond has passed after the Big Bang, our physics is in better shape and our models have made remarkable and verifiable predications. We view the Universe as an expanding ball of hot plasma in thermal equilibrium with small density variations imprinted from quantum phenomena ...
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 ...
Document
... object at the center of some galaxies that produces energy at a high rate- Quasar a neutron star that emits radio waves- Pulsar large celestial body that emits lights; Sun- Star the apparent shift in wavelength of light as the source moves away from or toward observer; Red and blue shifts- Doppler E ...
... object at the center of some galaxies that produces energy at a high rate- Quasar a neutron star that emits radio waves- Pulsar large celestial body that emits lights; Sun- Star the apparent shift in wavelength of light as the source moves away from or toward observer; Red and blue shifts- Doppler E ...
HERE - physicsisphun.org
... • Hotter objects glow with light of higher intensity at shorter wavelength. This light is more toward the blue or violet end of the visible light spectrum. • Cooler objects glow with light intensity at the longer wavelengths or more toward the red end of the spectrum. Spectral Lines and composition ...
... • Hotter objects glow with light of higher intensity at shorter wavelength. This light is more toward the blue or violet end of the visible light spectrum. • Cooler objects glow with light intensity at the longer wavelengths or more toward the red end of the spectrum. Spectral Lines and composition ...
Astronomy HOMEWORK Chapter 4 - University of San Diego Home
... 6. What is the Stephan-Boltzmann Law? How do astronomers use it? The Stephan-Boltzmann Law states that the total radiated energy of an object (or every square meter thereof ) increases proportional to the fourth power of the absolute (Kelvin) temperature. Astronomers use this to determine immediatel ...
... 6. What is the Stephan-Boltzmann Law? How do astronomers use it? The Stephan-Boltzmann Law states that the total radiated energy of an object (or every square meter thereof ) increases proportional to the fourth power of the absolute (Kelvin) temperature. Astronomers use this to determine immediatel ...
PHYS 390 Lecture 29 - White dwarfs and neutron stars 29
... of the binary pair has a mass now quoted at 1.05±0.03 solar masses, and a surface temperature (determined half a century later) of a very hot 27,000 K in spite of a luminosity just 0.03 that of our Sun. These observations can be taken together to paint a picture of an altogether different type of st ...
... of the binary pair has a mass now quoted at 1.05±0.03 solar masses, and a surface temperature (determined half a century later) of a very hot 27,000 K in spite of a luminosity just 0.03 that of our Sun. These observations can be taken together to paint a picture of an altogether different type of st ...
Homework 5
... In Shu 5.11 you computed how long it takes a photon to leak out of the sun. This is comparable to the time it would take all the radiant energy inside the sun to escape. As you’ve just shown, there’s much more energy than this present in the plasma, in the form of the kinetic energy of the particles ...
... In Shu 5.11 you computed how long it takes a photon to leak out of the sun. This is comparable to the time it would take all the radiant energy inside the sun to escape. As you’ve just shown, there’s much more energy than this present in the plasma, in the form of the kinetic energy of the particles ...
14_creationism
... • Birth: collapse of gas cloud forms protostar. • Main sequence: center of star becomes hot ...
... • Birth: collapse of gas cloud forms protostar. • Main sequence: center of star becomes hot ...
Our Sun - Stephen W. Ramsden
... Stellar fusion reactions gradually convert hydrogen into helium through the p-p chain. When a star runs out of hydrogen fuel, it either stops burning (becoming a dwarf star) or, if it is large enough (so that gravity compresses the helium strongly) it begins burning the helium into heavier elements. ...
... Stellar fusion reactions gradually convert hydrogen into helium through the p-p chain. When a star runs out of hydrogen fuel, it either stops burning (becoming a dwarf star) or, if it is large enough (so that gravity compresses the helium strongly) it begins burning the helium into heavier elements. ...
The Life Cycle of Stars Webquest
... 1. In this webquest, you will learn how to identify stars by their magnitude, color, temperature, and spectral class. 2. You will investigate the process of nuclear fusion explained by Einstein's famous equation E = MC2 and learn how mass in the form of hydrogen atoms is converted to helium and caus ...
... 1. In this webquest, you will learn how to identify stars by their magnitude, color, temperature, and spectral class. 2. You will investigate the process of nuclear fusion explained by Einstein's famous equation E = MC2 and learn how mass in the form of hydrogen atoms is converted to helium and caus ...
Name________________ Astronomy I cans 1. What is the Big Bang
... The dust and gas in a nebula began to spin, then the dust and gas began accreting (gathering) because of gravity ...
... The dust and gas in a nebula began to spin, then the dust and gas began accreting (gathering) because of gravity ...
Type II supernova
A Type II supernova (plural: supernovae or supernovas) results from the rapid collapse and violent explosion of a massive star. A star must have at least 8 times, and no more than 40–50 times, the mass of the Sun (M☉) for this type of explosion. It is distinguished from other types of supernovae by the presence of hydrogen in its spectrum. Type II supernovae are mainly observed in the spiral arms of galaxies and in H II regions, but not in elliptical galaxies.Stars generate energy by the nuclear fusion of elements. Unlike the Sun, massive stars possess the mass needed to fuse elements that have an atomic mass greater than hydrogen and helium, albeit at increasingly higher temperatures and pressures, causing increasingly shorter stellar life spans. The degeneracy pressure of electrons and the energy generated by these fusion reactions are sufficient to counter the force of gravity and prevent the star from collapsing, maintaining stellar equilibrium. The star fuses increasingly higher mass elements, starting with hydrogen and then helium, progressing up through the periodic table until a core of iron and nickel is produced. Fusion of iron or nickel produces no net energy output, so no further fusion can take place, leaving the nickel-iron core inert. Due to the lack of energy output allowing outward pressure, equilibrium is broken.When the mass of the inert core exceeds the Chandrasekhar limit of about 1.4 M☉, electron degeneracy alone is no longer sufficient to counter gravity and maintain stellar equilibrium. A cataclysmic implosion takes place within seconds, in which the outer core reaches an inward velocity of up to 23% of the speed of light and the inner core reaches temperatures of up to 100 billion kelvin. Neutrons and neutrinos are formed via reversed beta-decay, releasing about 1046 joules (100 foes) in a ten-second burst. The collapse is halted by neutron degeneracy, causing the implosion to rebound and bounce outward. The energy of this expanding shock wave is sufficient to accelerate the surrounding stellar material to escape velocity, forming a supernova explosion, while the shock wave and extremely high temperature and pressure briefly allow for theproduction of elements heavier than iron. Depending on initial size of the star, the remnants of the core form a neutron star or a black hole. Because of the underlying mechanism, the resulting nova is also described as a core-collapse supernova.There exist several categories of Type II supernova explosions, which are categorized based on the resulting light curve—a graph of luminosity versus time—following the explosion. Type II-L supernovae show a steady (linear) decline of the light curve following the explosion, whereas Type II-P display a period of slower decline (a plateau) in their light curve followed by a normal decay. Type Ib and Ic supernovae are a type of core-collapse supernova for a massive star that has shed its outer envelope of hydrogen and (for Type Ic) helium. As a result, they appear to be lacking in these elements.