Chapter three: The properties of Stars
... It is also found that the total energy rate is proportional to the 4 th power of the black body temperature: L AT 4 ...
... It is also found that the total energy rate is proportional to the 4 th power of the black body temperature: L AT 4 ...
Today The Sun Events
... End of Fusion • Fusion progresses no further in a low-mass star because the core temperature never grows hot enough for fusion of heavier elements (some He fuses to C to make oxygen). • Degeneracy pressure supports the white dwarf against gravity. • White dwarf spend eternity cooling off, eventuall ...
... End of Fusion • Fusion progresses no further in a low-mass star because the core temperature never grows hot enough for fusion of heavier elements (some He fuses to C to make oxygen). • Degeneracy pressure supports the white dwarf against gravity. • White dwarf spend eternity cooling off, eventuall ...
Stars III The Hertzsprung
... c) No, stars have similar lifetimes despite their different masses. d) No, more massive stars are much more luminous than low mass stars and use up their hydrogen faster, even though they have more of it. ...
... c) No, stars have similar lifetimes despite their different masses. d) No, more massive stars are much more luminous than low mass stars and use up their hydrogen faster, even though they have more of it. ...
Neutron Stars
... Periods shorter than this do not exist (such as in the previous calculation) because the object would have to rotate so fast it would overcome gravity and fly apart. ...
... Periods shorter than this do not exist (such as in the previous calculation) because the object would have to rotate so fast it would overcome gravity and fly apart. ...
Teachers` Manual - Amundsen High School
... smaller objects: asteroids and comets. All held in single system by Sun's gravity Sun's mass about 1000 greater than all other objects put together Solar System is essentially a disk All planets orbit Sun in same direction and in nearly same plane. ...
... smaller objects: asteroids and comets. All held in single system by Sun's gravity Sun's mass about 1000 greater than all other objects put together Solar System is essentially a disk All planets orbit Sun in same direction and in nearly same plane. ...
ASTR 1020 Homework Solutions
... 40. (a) For a frequency of 557 × 109 Hz, the wavelength is λ = c / ν = (3 × 108 m/s) / (557 × 109 Hz) = 5.4 × 10-4 m = 5.4 × 105 nm = 540 µm This radiation is in the far infrared near the microwave region (see page 101). (b) Because this radiation is strongly absorbed by the atmosphere (see page 14 ...
... 40. (a) For a frequency of 557 × 109 Hz, the wavelength is λ = c / ν = (3 × 108 m/s) / (557 × 109 Hz) = 5.4 × 10-4 m = 5.4 × 105 nm = 540 µm This radiation is in the far infrared near the microwave region (see page 101). (b) Because this radiation is strongly absorbed by the atmosphere (see page 14 ...
1 AST 104 LAB 1 Temperature and Luminosity of Stars: Wein`s Law
... To understand how thermal spectra can be used to evaluate the temperature of a star To understand how temperature and radius of a star determine a star’s luminosity Introduction: In this activity we will learn how light from a star can tell us its temperature and how much energy per second the s ...
... To understand how thermal spectra can be used to evaluate the temperature of a star To understand how temperature and radius of a star determine a star’s luminosity Introduction: In this activity we will learn how light from a star can tell us its temperature and how much energy per second the s ...
Stars are classified by their TEMPERATURE (color) SPECTRAL
... wavelengths it emits, we would expect luminosity plotted against temperature to make a straight line… There should be a one-to-one correlation between luminosity and temperature ...
... wavelengths it emits, we would expect luminosity plotted against temperature to make a straight line… There should be a one-to-one correlation between luminosity and temperature ...
phys-1600 - Dave Heppenstall
... has less dark lava flow patches. • Apparently, the earth's crust is thicker on the far side and topographically higher, thus preventing most of the lava flows from surfacing. Man on the moon • Seismometers placed on the moon during moon landings and we discovered that the moon's rocks are fundamenta ...
... has less dark lava flow patches. • Apparently, the earth's crust is thicker on the far side and topographically higher, thus preventing most of the lava flows from surfacing. Man on the moon • Seismometers placed on the moon during moon landings and we discovered that the moon's rocks are fundamenta ...
Spectral analysis for the RV Tau star R Sct: In this section, we will
... have luminosity classes of III, II, or I (where class II has properties in between III and I). Luminosity class V stars, like the sun, are main sequence stars and are generally used for reference as they do not vary and their intrinsic properties are well known. “By eye” we can see that the blue spe ...
... have luminosity classes of III, II, or I (where class II has properties in between III and I). Luminosity class V stars, like the sun, are main sequence stars and are generally used for reference as they do not vary and their intrinsic properties are well known. “By eye” we can see that the blue spe ...
Determining the Sizes & Distances of Stars Using the H
... massive than the Sun while the least massive ones are only 0.08 times the mass of the Sun. Most stars spend about 90% of their lifetimes shining due to nuclear fusion that goes on in their cores, but after awhile they evolve and begin to die. How long they live and what they evolve to become when th ...
... massive than the Sun while the least massive ones are only 0.08 times the mass of the Sun. Most stars spend about 90% of their lifetimes shining due to nuclear fusion that goes on in their cores, but after awhile they evolve and begin to die. How long they live and what they evolve to become when th ...
The classification of stellar spectra
... Late 1890s: at this time, the energy-level structure of atoms was not known. Stars were classified according to the strength of hydrogen Balmer lines with classes that were assigned a letter from A to O (from the strongest to the weakest). “Henry Draper Catalogue”, published by astronomers at the Ha ...
... Late 1890s: at this time, the energy-level structure of atoms was not known. Stars were classified according to the strength of hydrogen Balmer lines with classes that were assigned a letter from A to O (from the strongest to the weakest). “Henry Draper Catalogue”, published by astronomers at the Ha ...
Abstract - chara - Georgia State University
... stellar neighborhood they tend to dominate over more massive stars. This shows that the mass distribution function for all stars on the H-R diagram peaks at the low mass end and therefore the low mass stars are the most abundant. The lowest mass stars (spectral type M9) are capable of supporting the ...
... stellar neighborhood they tend to dominate over more massive stars. This shows that the mass distribution function for all stars on the H-R diagram peaks at the low mass end and therefore the low mass stars are the most abundant. The lowest mass stars (spectral type M9) are capable of supporting the ...
Stars change over their life cycles.
... will briefly block some of the other star’s light, providing a clue that more than one star is present. The illustration at right shows a binary star system that can be detected this way. Sometimes astronomers can also figure out whether a star is really a star system by studying its spectrum. ...
... will briefly block some of the other star’s light, providing a clue that more than one star is present. The illustration at right shows a binary star system that can be detected this way. Sometimes astronomers can also figure out whether a star is really a star system by studying its spectrum. ...
Astronomy 112: Physics of Stars Problem set 1 solutions 1
... has an atmosphere and reflects 20% of the light that falls on it, but absorbs the other 80% and, in the assumed steady state, radiates it as a blackbody. (a) Ignoring any greenhouse effect, what is the temperature of the planet? Solution: The solution to the planetary tempearture comes from assuming ...
... has an atmosphere and reflects 20% of the light that falls on it, but absorbs the other 80% and, in the assumed steady state, radiates it as a blackbody. (a) Ignoring any greenhouse effect, what is the temperature of the planet? Solution: The solution to the planetary tempearture comes from assuming ...
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.