Red Dwarfs and Barnard`s star. Their origin and significance to
... eye; however, it is much brighter in the infrared than it is in visible light. Barnard’s star is thought to be 10 billion years old and older than our galaxy. It must have been captured from elsewhere. Bernard’s star is travelling towards us at a very high speed. It will become closer to us than Pro ...
... eye; however, it is much brighter in the infrared than it is in visible light. Barnard’s star is thought to be 10 billion years old and older than our galaxy. It must have been captured from elsewhere. Bernard’s star is travelling towards us at a very high speed. It will become closer to us than Pro ...
Sun, Stars, HR Diagram
... Base your answers to questions 18through 20 on the diagram below, which shows two possible sequences in the life cycle of stars, beginning with their formation from nebular gas clouds in space. ...
... Base your answers to questions 18through 20 on the diagram below, which shows two possible sequences in the life cycle of stars, beginning with their formation from nebular gas clouds in space. ...
Jeopardy 2015
... gravitationally collapse, fragments,It heats up and spins faster. When the core temperature reaches 100 mill K, nuclear fusion begins (H into He). When outward pressure equals inward pressure the star enters the main sequence. ...
... gravitationally collapse, fragments,It heats up and spins faster. When the core temperature reaches 100 mill K, nuclear fusion begins (H into He). When outward pressure equals inward pressure the star enters the main sequence. ...
Universe Now - Course Pages of Physics Department
... • Between 0.17-1.33 M but the radius only slightly larger than the Earth’s a very dense object! • Evolutionary end state of about 97% of stars in our Galaxy (an estimate). • Most white dwarfs are composed of carbon, oxygen, and helium. The fusion reactions are over the matter is pulled together ...
... • Between 0.17-1.33 M but the radius only slightly larger than the Earth’s a very dense object! • Evolutionary end state of about 97% of stars in our Galaxy (an estimate). • Most white dwarfs are composed of carbon, oxygen, and helium. The fusion reactions are over the matter is pulled together ...
ASTRONOMY 161
... (4) The most abundant elements in the Universe are hydrogen and helium. It is fairly easy to determine which elements are present in a star. It is much harder to determine how much of each element is present. Strength of emission and absorption lines depends on temperature as well as on the element ...
... (4) The most abundant elements in the Universe are hydrogen and helium. It is fairly easy to determine which elements are present in a star. It is much harder to determine how much of each element is present. Strength of emission and absorption lines depends on temperature as well as on the element ...
Galaxies - C. Levesque
... • The new heat in the core fuses the helium into carbon • The outer shell still has some hydrogen and burns expanding to form a red giant or supergiant star • Once the core fuses into lead fusion stops and the star collapses. ...
... • The new heat in the core fuses the helium into carbon • The outer shell still has some hydrogen and burns expanding to form a red giant or supergiant star • Once the core fuses into lead fusion stops and the star collapses. ...
Astronomy 3020: Cosmology Samples for Exam 3
... a) As the solar nebula began to collapse under its own gravity it began to spinup due to the conservation of angular momentum. b) As the solar nebula began to collapse under its own gravity it began to flatten out into a disk shape with a central bulge. c) Protoplanetary disks are infant solar syste ...
... a) As the solar nebula began to collapse under its own gravity it began to spinup due to the conservation of angular momentum. b) As the solar nebula began to collapse under its own gravity it began to flatten out into a disk shape with a central bulge. c) Protoplanetary disks are infant solar syste ...
Homework #2
... temperature than Star B, how do the radii of both stars compare to each other? No numbers are needed, but justify your answer using a relation/equation from class. b) The star Rigel has a luminosity approximately equal to 105 L⊙ , and its radius is about 75R⊙. How does its effective surface temperat ...
... temperature than Star B, how do the radii of both stars compare to each other? No numbers are needed, but justify your answer using a relation/equation from class. b) The star Rigel has a luminosity approximately equal to 105 L⊙ , and its radius is about 75R⊙. How does its effective surface temperat ...
Aspire: Star Life Cycle - Easy Peasy All-in
... Our Sun Vega Sirius B I. Click on the image to start the next activity. ...
... Our Sun Vega Sirius B I. Click on the image to start the next activity. ...
types of stars, luminosity, and brightness
... intrinsic energy per sec that a star radiates and does not depend on our distance from the star. 7. Stars are classified by temperature and luminosity. 8. Supergiants are the most luminous and white dwarfs are the least luminous. 9. The main characteristic of main sequence stars is that they have hy ...
... intrinsic energy per sec that a star radiates and does not depend on our distance from the star. 7. Stars are classified by temperature and luminosity. 8. Supergiants are the most luminous and white dwarfs are the least luminous. 9. The main characteristic of main sequence stars is that they have hy ...
What is a Star? - Yale Astronomy
... density at “surface” of sun is MUCH MUCH lower than density of air! ...
... density at “surface” of sun is MUCH MUCH lower than density of air! ...
U7 Review WS KEY
... Despite all the gas, dust and stars in the universe, the universe is still mostly _empty space_. The sum of all matter, energy and space is _the universe_. Why do we think that dark matter exists? not enough visible matter in universe to account for effects of gravity due to mass. Einstein’s ...
... Despite all the gas, dust and stars in the universe, the universe is still mostly _empty space_. The sum of all matter, energy and space is _the universe_. Why do we think that dark matter exists? not enough visible matter in universe to account for effects of gravity due to mass. Einstein’s ...
9.1: THE SUN IN BULK PHYS 1401: Descriptive Astronomy Notes
... ✦ So, skipping the intermediate steps, at its core, the sun fuses hydrogen into helium ✦ 600 million tons of mass per second are converted ✦ At that rate, the sun will only last another 5 billion years Observations of Solar Neutrinos ✦ Neutrinos are magic! ✦ No they aren't. But they are evidence of ...
... ✦ So, skipping the intermediate steps, at its core, the sun fuses hydrogen into helium ✦ 600 million tons of mass per second are converted ✦ At that rate, the sun will only last another 5 billion years Observations of Solar Neutrinos ✦ Neutrinos are magic! ✦ No they aren't. But they are evidence of ...
White Dwarfs and Neutron Stars
... • Degenerate stars heavier than 1.4 solar masses collapse to become neutron stars • Formed in supernova explosions • Electrons are not separate – Combine with nuclei to form neutrons ...
... • Degenerate stars heavier than 1.4 solar masses collapse to become neutron stars • Formed in supernova explosions • Electrons are not separate – Combine with nuclei to form neutrons ...
White Dwarfs and Neutron Stars
... • Degenerate stars heavier than 1.4 solar masses collapse to become neutron stars • Formed in supernova explosions • Electrons are not separate – Combine with nuclei to form neutrons ...
... • Degenerate stars heavier than 1.4 solar masses collapse to become neutron stars • Formed in supernova explosions • Electrons are not separate – Combine with nuclei to form neutrons ...
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.